Café posts split from Stormy Lagoon Nebula (19Oct)

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Post by apodman » Sun Oct 26, 2008 2:32 am

starnut wrote:people on the religious right ... angered by the devaluation of the stature of man and the special place we supposedly occupy in God's creation ... have tried to rise doubts about scientific findings ... and provide alternative ... unproven "theories".
So in the field of cosmology which is subject to a lot of question and in a discussion of cosmology which thrives on question and argument, we need to differentiate that kind of doubt-raising from criticism and probative inquiry raised on a scientific or other logical basis.

Surely scientific and logical argument have a different style and tone from a non-scientific attack, and they elicit responses with a different style and tone as well. Attacks, as opposed to questions and arguments, need no response; responses ranging from placating to insulting the insurgent do little to change the tone or content of the follow-up attack.

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Post by emc » Sun Oct 26, 2008 11:29 am

starnut wrote:
emc wrote:
starnut wrote:... The scientists haven't found all the answers yet, but yet the religious nuts insist that what the scientists know so far proves they are wrong, like for example the gaps in fossil records.

Gary
Hi Gary,

I think from reading your comment that you may be calling me a religious nut… if so, I am offended… Just plain “nut” would have been OK.

Even though I am not a scientist, if you read my posts here, you will know that I have a deep respect and appreciation for science. And I am not remotely trying to prove science or scientists wrong… I'm sorry I let my emotions get the better of me in this thread and expounded religious flavored cafe rhetoric. I simply look for truth as best I can. And what's wrong with looking in a public scientific forum?

I’ve had a lot of fun and learned a good deal of science, but I have frequently felt over my nutty head here.
emc, I apologize for offending you. I know that you have made a lot of interesting and thoughtful posts. I haven't seen any anti-science rants from you in them. There is nothing wrong with having a religious belief. My missive was aimed at people on the religious right who are angered by the devaluation of the stature of man and the special place we supposedly occupy in God's creation that scientists since Copernicus brought about. Those people have tried to rise doubts about scientific findings, particularly in the fields of biology, geology, and cosmology, and provide alternative explanations, such as creationism. intelligent design, electric universe, and other unproven "theories".

Gary
No prob Gary,

Thank you for the apology even though I see you weren’t writing to me directly.

I agree with you, that there are way too many religious folks still expounding that man is somehow the center of the universe and more important than any other life form.

For me, all life is sacred, even the bugs that I annihilate with my windshield. :( I simply ask for forgiveness and keep plowing ahead.

As far as the raising of doubts by the religious community toward the scientific community… isn’t that kind of like a review test, say a social test that could potentially help integrate conflicting evidence into a belief system that may need a paradigm shift? Integration takes time, especially if there has to be a change in perception. It was believed that the sun rose for a quite a while and we still speak as if it were true.

Unfortunately, religious people are a lot of times trying to assert their personal beliefs onto others… I think certain sects misinterpret their own dogma by doing this and set out to annoy the world although they have good intentions. This is seldom a successful means of changing anyone’s mind and usually has the opposite effect.
Last edited by emc on Sun Oct 26, 2008 11:45 am, edited 1 time in total.
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Post by emc » Sun Oct 26, 2008 11:37 am

apodman wrote:
emc wrote:I am struggling to keep up but let me see if I’m still in the ballpark with you guys… I feel like I'm in the “nose bleed” section :wink: (if you don’t know – ‘nose bleed section’ is the furthest seats in a stadium without actually being outside)
We (forum folks, scientists, et al.) are all in the cheap seats. Else someone would have cosmology all tied up with a neat bow in an elegant theory that would make us all happy.
emc wrote:As a layman, I see astrophysics and cosmology as high level science. By ‘high level’ I mean similar to particle physics… on the edge of discovery almost constantly… at least that’s my perception.
Do you think cosmology is headed in the right direction? I look at something as disturbingly complex as superstring theory and find it aesthetically appealing, so a convoluted explanation is apparently not an impediment to my becoming a fan (still in the stadium, Ed). But a large-scale universe full of things I can't see that nobody ever heard of when I went to school needs something appealing to offset the cold dark strangeness of it all. So I look for some neat and complete mathematical explanation, and they say we're working on it, we'll get it to you.
I’m not a good resource to answer that question so I will just make a stupid joke and hope you don’t mind. Cosmology is headed in the right direction if, from the USA for example, we don’t try and observe through China.

But since I like to hear myself write, I will expound a bit… I have a lot of difficulty understanding the information I read about science - especially when they get above 9th grade level such as string theory, it likely disturbs my head more than yours. I have perceived from your writings that you are among the Asteriskers that reside over my 'scientific' head… say that does put you in the cheap seats doesn’t it? :wink: Maybe I haven’t read enough about string theory to filter it into my brain? I think it is wonderful that people are able to think of such things in the first place. I suppose it is some logical progression or branching into an idea that is hoped to provide more insight into the mesmerizingly beautiful eloquence of how the universe works.
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Post by apodman » Sun Oct 26, 2008 2:45 pm

emc wrote:
apodman wrote:Do you think cosmology is headed in the right direction?
I’m not a good resource to answer that question
You're just who I wanted to ask, as you have volunteered for the "humble layman in this discussion" role and performed it with verisimilitude. In other words, the one with the least bias approaching the question.

The lame open phrasing of the question is purposeful, too. I want the least bias possible from anyone who would care to answer it.

And level of knowledge is not an issue. Here in the cheap seats we're all over 0% and nobody's 100%. All our opinions are based only on what we know and what we've heard, however much that is. If Einstein's ghost's vote counts more than that of whomever invented the wheel, we can worry about the electoral formula later.

So here I go paraphrasing again: If your final-answer-Regis is that "some of what I hear about astrophysical cosmology is somehow beyond my understanding, comprehension, grasp, or vision, and my education on the subject is not complete", that's my answer too.
emc wrote:... among the Asteriskers that reside over my 'scientific' head
I admit to having exposure to many subjects (including some we discuss here) in varying depth, but much is smoke and mirrors. I often find I have just enough background knowledge and scanning skills to make quick applicability judgments on the results of an internet search. If the links add up easily to successful research, I stick it together with some slick words and post it. If they don't, I don't report yet another dead end - you simply don't hear from me and I'm apparently just leaving the "expert" reply to someone else. For what it's worth, a couple of contributors are coming to mind who, when they get on a roll, appear to be at least as far over my head as I am over the most uninformed person on the planet. I respect you all, but I'm simply blown away technically by some. Just ... too ... many ... gaps ...
emc wrote:Maybe I haven’t read enough about string theory to filter it into my brain?
Or maybe I was lucky enough to stumble into a great explanation. Of course I can't find it now.

---

P.S. Thank you Ed for your contributions of sensible perspective regarding science and religion (among other subjects). It is not so unusual for us thinking humans to live comfortably in both the spiritual and physical worlds, regardless of what those with extreme views have to say. I am often tempted to say something, but I don't think I have a delivery on that subject that would go over well. So thank you for volunteering for that role too.
Last edited by apodman on Sun Oct 26, 2008 3:50 pm, edited 2 times in total.

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Post by Nereid » Sun Oct 26, 2008 3:22 pm

So many interesting posts, so many great lines of thought to pursue, :)
... so little time! :cry:

Perception

I'd like to continue with this, and come back to 'perception = what you see', as in 'sense of sight'.

The connection between what you see on your computer screen (etc) and your acceptance (I'll address 'acceptance, at some level', 'belief', and 'faith' later) that some person typed letters on a keyboard somewhere else in the world some time earlier is mediated by an acceptance that everything about the relevant technology 'works'. Or perhaps it's stronger - at some level, acceptance of the technology (etc) is essential.

Of course, that acceptance of the technology (at some operational level - 'it works') could be no different than 'magic'. And that's undoubtedly the basis of many people's acceptance. And that's fine, OK, allright, ... but if so there would not be much content to any discussions here the The Asterisk*, would there? So I'll leave 'magic done it' aside from now on.

Connecting (acceptance of) technology which works to scientific theory, for stuff like the internet, is reasonably straight-forward, and while there are one or two logical caveats that may need to be entered^, I'll assume (for now at least) that I can leave readers to fill it in for themselves.

Maybe you're thinking 'how insanely pedantic can you get!' or 'what does accepting that people somewhere else in the world sat down at a computer keyboard and typed posts have to do with scientific theories?!'

Here's the point: your sense of sight is your window to the world of people typing posts to The Asterisk*, but those people (and their posts) are only real if a great deal of scientific theory is also real (assuming no perception of any of these people in ways other than reading their posts on your computer monitor).

^ e.g. something like "sure the technology works, but the relationship with the underlying scientific theory is only random ... blind luck" or "the theory's only approximately relevant, 'cause engineers are always making tweaks and adjustments that you can't explain with the textbook scientific theory"

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Post by Nereid » Sun Oct 26, 2008 3:35 pm

Acceptance, Belief, etc

I've used 'at some level' several times in my posts; in this post I'd like to say a bit more about this, and distinguish among acceptance, belief, faith, etc.

First, I'm going to take 'belief' ('believe') and 'faith' right out of my discussions ... they work at a different level than the 'acceptance' I am interested in.

For example, for my purposes, you can 'believe' something without 'accepting' it, and vice versa (perhaps you accept that GR provides an excellent description of how mass-energy 'works', but believe that it's really aliens messing with our minds, to turn the contrast waaaay up).

The 'acceptance at some level' I am interested in concerns, ultimately, the scope and nature of scientific theory (which I haven't yet described clearly), and logic. One of the things I hope to get to is axioms, or core assumptions; this will also open discussion of Popper, falsificationism, etc.

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Post by apodman » Sun Oct 26, 2008 3:43 pm

Nereid wrote:'how insanely pedantic can you get!'
Like I told emc, I have scanning skills. This was the first line to jump out of your post at me, though you buried it in the middle. Apparently I expect this exact reply to every post I make, and I'm very sensitive or paranoid as well as an automatic mechanical scanner. So I was greatly relieved to see it was not addressed to me - this time.
Nereid wrote:Here's the point: your sense of sight is your window to the world
They say people like their information by vision, hearing, or touch (doing). Some like a combination. I'm almost completely visual myself, both in the way I like my information input and the way I organize abstractly in my mind. So I can relate to the metaphor and example of the computer screen as my input terminus on the information pipeline.
Nereid wrote:"the theory's only approximately relevant, 'cause engineers are always making tweaks and adjustments that you can't explain with the textbook scientific theory"
Now that is the kind of pure refined bull!@#$ that I see from "scientists" and non-scientists alike in the real world. Great example. Maybe we can forgive the non-scientists, but it really irks me when I see supposedly intelligent people saying something like that.
Last edited by apodman on Sun Oct 26, 2008 4:05 pm, edited 2 times in total.

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Post by Nereid » Sun Oct 26, 2008 3:56 pm

Taking some earlier posts ...
emc wrote:[...]
Nereid wrote:Second, for the subset of APOD 'pictures' that are 'out of this world' (i.e. from space probes, or of planets - other than Earth, stars, galaxies etc), how much does your perception of what's in the pictures depend on theory (leave aside how the pictures got from some server in MTU to your screen/monitor)?
2. Very little. I see the pictures aesthetically… as works of art... both from the author of the APOD and the Author of the APOD subject.
To clarify, if I may ... the 'stars' (in various APODs) may be 'other Suns', or they may be something else entirely, it's pretty much a wash for you?

NGC 7331 may be 'warped' in some sense, or not; someone may be able to write a few words on how you could find out, assuming it's 'really' a lot of stars (and gas and dust) a long way away, to some level of certainty, but so what?

The Big Bang may have created all the stuff which later became the stars and gas and dust in the Lagoon nebula, or some space aliens created a neat screen in front of the HST just before it snapped that picture which became the 19 Oct 2008 APOD (but who cares)?
[...]
Nereid wrote:Fifth, is 'proof' possible, in science? If so, what are the criteria for judging if something is '(scientifically) proven'? If not, why not?
5. Sure, science through the use of evolved telescopes and other tools proved that insects and vegetation doesn’t exist on the moon which was a theory by astronomer William Henry Pickering (February 15, 1858 – January 17, 1938). I don’t know how to list the criteria except lack of evidence debunked the theory.
Have you heard of 'the problem of induction'?

You may have observed many apples falling, and read many accounts of many other people who said they saw apples falling. From this you may infer something about apples and falling (via inductive reasoning), but surely you cannot 'prove' that (all) apples do indeed fall?

Science needs to address this problem somehow; I think a common way is to leave 'proof' out of it, another is to re-define 'proof' so it has a much weaker meaning.

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Post by Nereid » Sun Oct 26, 2008 4:07 pm

apodman wrote:Theory and Perception

I view everything in terms of my current understanding. This includes scientific theory.

If I don't know anything about a particular idea, it has no influence on my perception. With respect to that idea, my consideration of any phenomenon or object is a blank slate.

If I know something about a particluar idea but haven't gotten to the point of supporting or opposing it, my perception can benefit from seeing a phenomenon or object in the light of the information that comes with the idea.

If I know enough about an idea (or think I do) to have formed an opinion, I can benefit from the information but I introduce the element of prejudice or bias into my perception.

Something that agrees with my preconceptions makes me more receptive to new information, and something that disagrees makes me unreceptive. The countermeasure for prejudice is openmindedness, which is the attempted willing temporary suspension of my opinion so I can reap the same informational benefits as a naturally receptive (unbiased) person.

Theory and Perception of APOD Content

The general statements above apply.

APOD content often illustrates or attempts to illustrate a theory. This can be the main purpose of the APOD, or might be any of the theories implicit in the picture. Dispensing with bias as well as I can, I hope to consider any idea presented to me. Usually I'm successful because I don't come looking for an argument and I don't keep digging until I find one.

[...]
If I may explore this a bit, with a specific example, within the framework of my earlier posts about perception (etc).

The 17 Sep 2008 APOD is of MACSJ0025.

Let's call it 'a visual representation of data' taken with the HST and Chandra.

Some of the data went through the usual data processing pipelines from detection aboard the spacecraft to display in .jpg format on your screen.

Some of the data went through a very different path, to end up as the diffuse blue blobs in the image.

In the sense that your acceptance of real persons elsewhere in the world typing posts depends on scientific theory (the internet etc), what level of acceptance of scientific theory is there, for you, at some level, for this APOD?

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Post by apodman » Sun Oct 26, 2008 4:33 pm

Nereid wrote:The 17 Sep 2008 APOD is of MACSJ0025.

... what level of acceptance of scientific theory is there, for you ... for this APOD?
Wow. My first reaction to this picture was "what is it?". So I read the explanation, and my first reaction was "I can't just absorb this one lazily and understand it". Without reviewing my posts on this APOD, I'm sure they reflect how slowly I came to an understanding of what I was looking at and what I was being told.

So my level of acceptance of scientific theory in perceiving this APOD is not much beyond an open (and barren) mind trying to grok what is before me. The dark matter concepts are still new to me, I can't digest them fast enough to form an intelligent opinion, and I don't know enough at this point to accept or reject the propositions presented to me. But I provisionally accept what I'm being told as at least an explanation worthy of consideration, and I'm happy to have that much more background (even if my understanding of it is still sketchy) to help me better know what to accept when I am told something related in the future (hopefully soon). This all sounds to me like it falls under the heading of "attitude".

To be clear, I accept a whole bunch of scientific theory about the subject matter (galaxies, gravitational lensing, etc.) and about the data-gathering instruments and methods before getting started on the point of the picture and explanation.

Also to be clear, this particluar APOD presents at least a double challenge: First I have to get my brain around the question of dark matter. Second I have to get my brain around the question of the validity of the logic used to draw conclusions from the combined visual and x-ray data. Meanwhile, to visualize the collision, I have to use my own imagination to project positions back in time from those illustrated in the still picture.

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Post by Nereid » Sun Oct 26, 2008 6:05 pm

apodman wrote:
Nereid wrote:'how insanely pedantic can you get!'
Like I told emc, I have scanning skills. This was the first line to jump out of your post at me, though you buried it in the middle. Apparently I expect this exact reply to every post I make, and I'm very sensitive or paranoid as well as an automatic mechanical scanner. So I was greatly relieved to see it was not addressed to me - this time.
Having a conversation, or discussion, on the internet, within the confines of phpBB forum software, can be very difficult ... not least because sometimes one reads too much into the plain words on the screen.

If I may add a few clarifications?

While I may quote some posts, or parts of them, and comment, I'm usually not directing my comments at one person (either the author, or through the author at someone else).

Second, I hope my intent of discussing the ideas is understood ... I may write two wildly contradictory ideas, even in a single post; you* may say one (or both) are balderdash and poppycock, or that I am being deliberately offensive ... the former is fine (though I'd hope you* put some flesh on the bare bones!), the latter not (the ideas I write do not have 'deliberation'; if you* find some ideas offensive, you* should say why).
Nereid wrote:Here's the point: your sense of sight is your window to the world
They say people like their information by vision, hearing, or touch (doing). Some like a combination. I'm almost completely visual myself, both in the way I like my information input and the way I organize abstractly in my mind. So I can relate to the metaphor and example of the computer screen as my input terminus on the information pipeline.
When it comes to 'out of this world' astronomy, sight is really the only sense that matters ... light is for seeing with eyes; generalised light (electromagnetic waves, or photons) is for representing visually.

Of course, data can be represented so we perceive it using our sense of hearing, or touch, or even smell and taste (or some combo); for convenience, sight should be able to serve as a shorthand for all the senses, shouldn't it?
Nereid wrote:"the theory's only approximately relevant, 'cause engineers are always making tweaks and adjustments that you can't explain with the textbook scientific theory"
Now that is the kind of pure refined bull!@#$ that I see from "scientists" and non-scientists alike in the real world. Great example. Maybe we can forgive the non-scientists, but it really irks me when I see supposedly intelligent people saying something like that.
Hehe :lol:

It is important to include these sorts of caveats, even if we don't get around to discussing them.

Believe it or not, I was in a discussion, once (not here), with someone who used this approach as part of a 'GR isn't supported by the evidence!' case ... so there is at least one person who takes this caveat quite seriously.

* not you, apodman, but you the reader in general.

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Post by apodman » Sun Oct 26, 2008 6:27 pm

Nereid wrote:When it comes to 'out of this world' astronomy, sight is really the only sense that matters ... light is for seeing with eyes; generalised light (electromagnetic waves, or photons) is for representing visually.
Photon junkies 'r' us scientists.
Nereid wrote:sight should be able to serve as a shorthand for all the senses, shouldn't it?
Absolutely. And for the senses extended by technology as well.

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Post by Nereid » Sun Oct 26, 2008 6:55 pm

Commenting on some more older posts ...
bystander wrote:[...]
Theory and Fact

Theory and fact are two different things. Fact is tangible. Theory is just our interpretation of those facts. How well that theory explains the facts or makes predictions about future observations determines how well received that theory becomes. Sometimes theory can become so well received that it may be perceived as fact. To the layman, it may become indistiguishable from fact. This is a fault of our educators and the science community.
If we look at the APOD I referenced a bit earlier (MACSJ0025, APOD 17 Sep 2008), how deeply entangled would you say fact and theory are?

My own view - which I enjoy discussing - is that 'fact' in modern astronomy is so thoroughly soaked with (or, if you prefer, dependent upon) 'theory' as to make the distinction essentially useless in almost all of modern astronomy, in the sense that one could do some interesting astronomy based on 'theory-free' facts.

It is probably easier to discuss this around 'observations' than 'facts'; other than observations you make with your own eyes, unaided by even spectacles/glasses, do you think there are any pure observations? In the sense that their status as observations does not require the acceptance, at some level, of at least some scientific theory? I appreciate that fleshing out what 'scientific theory' means, here, is important to nailing this down properly.
Past vs. Present

In a very real sense, it's all science of the past. By the time we begin to study a phenomenon, it has already passed, but I don't think that is what's being asked. Study of the past helps us in understanding where we are today. Geology, archeology, paleontology, and even history give us an understanding of how our home planet has changed. Astrophysics and cosmology give us the bigger picture of the universe in which we live. History of science provides us with a view of how our understanding of the world has evolved.
This is another place where I think we need a very powerful tool, akin to the one (or ones) that helps us with the problem of induction I mentioned earlier.

FWIW, this is an area which I think Karl Popper tripped up on, big time (to oversimplify, if you make something like falsificationism a critical part of what science is, then science cannot study 'the past', at least in some respects).

This question has a particular pertinence to astronomy and cosmology, because we can 'see' only the past (due to the finite speed of light), and even with good historical records, we cannot directly observe changes that have taken place more than a thousand light-years or so away. Of course, there are techniques which allow fascinating reconstructions of the past, and which also allow testable hypotheses to be developed: the Sun-grazing comets observed by SOHO lead to predictions about earlier passages of bright comets which lead to targetted searches in historical records (Chinese, Japanese, Korean) ... which turned up historical observations of them! Light echoes allow us to watch an ancient supernova explode anew and "Using only raw pixel data and known catalog proper motions, it is possible to accurately estimate the date of origin of historical imagery" to take just three examples.
Scientific Proof

Scientific proof is possible, but only in the negative. One of the tenets of the scientific method is falsifiability. With only one observation that contradicts a theory, that theory can be proven wrong. However, unlike mathematics, proving a scientific theory right is impossible. Regardless of the preponderance of evidence, how useful a theory is in making predictions, or how plausible a theory may seem, it is still only a theory and will never be fact.

[...]
This idea is, I think, quite widespread; it's also quite wrong, in terms of how modern science actually works.

In fact, in its 'naive' form, falsifiability can be used directly to falsify this Popperian 'theory' (of science), thereby proving (in the limited sense of bystander's comment) that the (Popperian) theory is wrong.

Here are three examples:

Applying (Newton's) theory of gravity to observations of Uranus produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. You, dear reader, know the rest, don't you?

Applying (Newton's) theory of gravity to observations of Mercury produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. Ditto.

A great many, very good, observations of certain 'beta decays' 'contradicted' the 'theory' of conservation of energy, in the 1920s and 1930s; ergo it was 'proven wrong'. Pauli saved the day with a wild idea (the little neutral one), and Cowan and Reines got a Nobel for, ... well, for what exactly? This example is quite interesting, wrt falsifiability, in many respects; for example, was the theory of conservation of energy falsified until 1957 (at least wrt certain beta decays)? or until ~2000 (when the 'solar neutrino problem' was resolved)? In Popper's theory, how to account for 'not-falsified' -> 'falsified' -> 'not-falsified' (etc) cases?
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Post by Nereid » Sun Oct 26, 2008 7:13 pm

emc wrote:
Nereid wrote:If I may, I'd like to dive into the relationship between perception and theory a bit.

And to start I'll limit 'perception' to (the sense of) sight.

Much of what follows may seem pedantic or philosophical (or both, or worse), but it's important for the point I'd like to (eventually) make.

I imagine each of you reading this is looking at a computer screen or monitor (or perhaps on an iPhone or similar), and at some level you accept, as 'reality', that a person, somewhere else in the world (other than in the place you are now reading this) typed these words - used their fingers to press keys on a keyboard of some kind. You also acknowledge, at some level, that how those keystrokes became patterns on the screen that you are reading involves some technology - the manufacturing of the keyboard and computer, the delivery of electricity, 'the internet', and so on.

But what else is involved in your acknowledgement of the role 'technology' played in your acceptance of the reality I just sketched?

Specifically, at some level, how many, or what, scientific theories does your acknowledgement implicitly require you to accept? Or, to step back a bit, to what extent do you agree that acknowledgement of 'technology' requires acceptance of (at least some) scientific theory, at some level, if only implicitly?

To jump ahead: I am interested in how strongly a case can be made that the kind of acknowledgement of technology that is involved in 'using the internet' means acceptance of modern, mainstream astrophysics (with some important caveats). A possible corollary is that a rejection of 'the Big Bang' (properly re-phrased in terms of contemporary cosmology, the science) is, logically, equivalent to a denial that you 'use the internet'.
Let me see if I get your point… I accept the use of the technology that goes into the internet by using it so I am also accepting the scientific theories that are embedded throughout technology.
Yes.

To parse it a bit more ... there are some (logically valid) caveats ('magic', for example), some of which I covered in posts I wrote a bit earlier today.

Also, 'at some level'. At a minimum there needs to be at least an implicit acceptance of the validity of simple logic.

Further, to be pedantic, my point was limited to your acceptance of the idea that a person somewhere else in the world, some time earlier, pressed keys on a keyboard (or similar) corresponding to the words you read on your monitor (or similar). In practice this itself is powerful enough to encompass just about all of the foundation theories in modern physics (though there are parts of the Standard Model of particle physics that are quite unnecessary)!

Finally, it is surely possible to build a logically consistent case using a much more restricted set of scientific theories whose acceptance would be needed (given the premise), but even the most cogent of 'alternatives' surely gets only a percent or two of the way towards doing that. And anyway, the people who designed, manufactured, installed and who maintain the myriad of gadgets and systems that you use most assuredly relied upon textbook physics.

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Post by Nereid » Sun Oct 26, 2008 7:18 pm

Last comment on an older post, for today.
Chris Peterson wrote:
Nereid wrote:The relationship between "reality" and (scientific) theory is an interesting one. As it's come up in this thread, let me ask all readers some simple questions, if I may.
I'll consider those questions in a moment, but first, a comment on the above. In my view, "reality" is what we observe, and "theory" is what we use to explain or predict our observations. I don't think that theory in itself needs to have any connection with reality, other than explaining it. That is, if a theory describes an observation in some mathematical terms, there is no requirement that the math and reality have any true connection. Reality just is. I don't find it necessary to ask why- I don't even think the question is necessarily meaningful. Why does gravity cause two masses to attract each other? Meaningless question. Theory can describe the process, but the Universe doesn't solve Newton's equation (or some GR tensor) for every particle, I'm pretty sure of that!

[...]
I've started to comment more about this ('fact' vs 'theory', bystander's post, for example), and I'd very much like to continue.

For now though, if I may, what (for you) is a 'theory-free' observation, in modern astronomy?

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Post by apodman » Sun Oct 26, 2008 7:18 pm

Nereid wrote:In fact, in its 'naive' form, falsifiability can be used directly to falsify this Popperian 'theory' (of science), thereby proving (in the limited sense of bystander's comment) that the (Popperian) theory is wrong.
Self-falsifying theories about theories? I yearn for the good old days (a few minutes ago) when all I didn't understand was dark matter. See what you started, Ed?
Nereid wrote:what (for you) is a 'theory-free' observation, in modern astronomy?
I don't know where you draw the line on "modern", but even with regular old fashioned observational astronomy I think there's no such thing as 'theory-free' observation.

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Post by Nereid » Sun Oct 26, 2008 7:49 pm

OK, I lied; one more for today ...

I've just re-read this thread from the beginning, and I see that neufer, Sputnick, and orin stepanek posted to it before it was split from the original (Discuss an APOD) thread and moved here ("Wed Oct 22, 2008 3:44 pm"). These three folk have also not posted to this thread since then.

If any of you are still reading this, may I invite you to participate?

I'm particularly interested to hear from you Sputnick, because it seems (to me) that you have some (strong?) opinions about theory, observations (facts), science, cosmology, etc.

And although starnut has posted since 22 Oct, the one post has not been about any of my posts; may I explicitly invite you to comment too?

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Post by Chris Peterson » Sun Oct 26, 2008 10:16 pm

Nereid wrote:Applying (Newton's) theory of gravity to observations of Uranus produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. You, dear reader, know the rest, don't you?

Applying (Newton's) theory of gravity to observations of Mercury produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. Ditto.

A great many, very good, observations of certain 'beta decays' 'contradicted' the 'theory' of conservation of energy, in the 1920s and 1930s; ergo it was 'proven wrong'.
I'm afraid I don't understand how these examples argue against the idea of falsifiable theories.

The observations of Uranus did not in themselves falsify Newton's theory of gravitation. What they did was present a question: is Newton wrong, or is their another gravitational influence we are unaware of? Given the existing strength of evidence for Newton, the reasonable conclusion was the latter. Of course, had a search continued for long enough without finding anything, this would have started shifting support away from Newton. But the observation alone was not (and could not) be sufficient to falsify Newton's law.

The observations of Mercury did, in fact, correctly falsify Newton (although that had largely already been done). Of course, they served to bolster the support for GR, which extends Newton under particularly conditions. That is, Newton wasn't actually falsified. Rather, the conditions under which the law is applicable were more accurately defined.

The observations of beta decay behavior presented a similar question to what I posed above: is conservation of energy wrong, or is there another explanation? Of course, it drove the development of additional theory and did not invalidate conservation of energy.

These examples don't argue that theories can't be invalidated, only that the conditions of falsifiability need to be carefully defined. Observations can be misinterpreted, and that's something that has to be guarded against. When an observation appears to contradict a theory (especially a very strong theory), it is important to make sure that the observation has been interpreted in the only possible way.

If you examine well crafted modern theories, they include- from the beginning- cases that would falsify these theories. That is quite different from accidental observations that appear to invalidate some theory. Those need to be evaluated very carefully.
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Post by Nereid » Sun Oct 26, 2008 11:05 pm

Chris Peterson wrote:
Nereid wrote:Applying (Newton's) theory of gravity to observations of Uranus produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. You, dear reader, know the rest, don't you?

Applying (Newton's) theory of gravity to observations of Mercury produced inconsistencies; not one but hundreds of observations 'contradicted' the Newtonian theory, ergo it was 'proven wrong'. Ditto.

A great many, very good, observations of certain 'beta decays' 'contradicted' the 'theory' of conservation of energy, in the 1920s and 1930s; ergo it was 'proven wrong'.
I'm afraid I don't understand how these examples argue against the idea of falsifiable theories.
I'm pretty sure they don't ... nor were they intended to! :o

The context of my comments was a comment on bystander's "With only one observation that contradicts a theory, that theory can be proven wrong".

That's one way to summarise a version of falsificationism (called 'naive falsificationism') that is, unfortunately I suspect, all too common. Note that Popper himself was far too good a thinker to have ever proposed this version (except, perhaps, as a foil).

Let's explore this further ...
The observations of Uranus did not in themselves falsify Newton's theory of gravitation. What they did was present a question: is Newton wrong, or is their another gravitational influence we are unaware of? Given the existing strength of evidence for Newton, the reasonable conclusion was the latter.
Indeed.

But how do you decide - ahead of time - what constitutes a "reasonable conclusion"? And how do you measure "strength" (of evidence)?

Clearly, to be a good (or at least a useful) theory of science, falsificationism needs to have some caveats appended, some bells and whistles added.
Of course, had a search continued for long enough without finding anything, this would have started shifting support away from Newton. But the observation alone was not (and could not) be sufficient to falsify Newton's law.
How long would "long enough" have been? 1850? 1900? 2050??

Another aspect: perhaps Uranus is (was) "an anomaly"? Everything else moved just as Newton ordered, both within the solar system and beyond. Should the textbooks have then said "Newton's universal law of gravitation (except for Uranus)"?

And then there's this: it wasn't just one or two observations (of the position of Uranus), it was already hundreds (by the second half of the 1840s), and very precise ones they were, and independent (different observers, different observatories, etc).
The observations of Mercury did, in fact, correctly falsify Newton (although that had largely already been done). Of course, they served to bolster the support for GR, which extends Newton under particularly conditions. That is, Newton wasn't actually falsified. Rather, the conditions under which the law is applicable were more accurately defined.
The history is a little murkier ... the observations showing inconsistency with Newton were both extensive and precise several decades before Einstein was concluding his work on GR. And 'the Neptune solution' had been tried ("Vulcan"), and at the time it seemed to work, sorta.

A couple of follow-on questions, if I may:

* what do you mean by "although that had largely already been done"? AFAIK (as far as I know) the anomalous advance of the perihelion of Mercury was the only well-established observational or experimental result that 'falsified' (to be anachronistic) Newton, before publication of GR

* in terms of content, GR couldn't be more different than Newtonian gravity! The latter is an 'action at a distance', an (instantaneous) force; the former is geometry. Sure you can show that GR 'reduces to' Newton in the appropriate limit, and so that is good enough for that region of parameter space. But to say that "Newton wasn't actually falsified" surely adds some rather sweeping restrictions to "falsify" doesn't it?
The observations of beta decay behavior presented a similar question to what I posed above: is conservation of energy wrong, or is there another explanation? Of course, it drove the development of additional theory and did not invalidate conservation of energy.

These examples don't argue that theories can't be invalidated, only that the conditions of falsifiability need to be carefully defined. Observations can be misinterpreted, and that's something that has to be guarded against. When an observation appears to contradict a theory (especially a very strong theory), it is important to make sure that the observation has been interpreted in the only possible way.
Indeed.

But doesn't that raise rather knotty questions? Such as "what constitutes misinterpretation of a theory"? and "to what extent can the 'conditions of falsifiability' be defined beforehand"?

Of course, it is easy, almost trivially so, to look backward and write a history of the development of one or other theory (in physics), using falsifiability as a guiding principle. However, how can - could - this concept be applied, in any useful way, when you're in the middle of things?

Take a (just barely historical) example: the Pioneer anomaly.

If we had a time machine, we might read in (future) textbooks of physics that this was pivotal in the discovery of a theory of gravity that replaced/extended GR. I.e. it 'falsified' GR.

Or we may read, as a mere footnote in just a fraction of those (future) textbooks that this 'so-called' anomaly turned out to 'nothing more' than a combination of poor modelling and noisy data. I.e. it did not 'falsify' GR.

Or ...

The point is, how can we tell - today - what the (future) status of 'the Pioneer anomaly' is?

Reading the history of 'the solar neutrino problem' is quite sobering (or uplifting, or ...), when considered with 'falsifiability' in mind.
If you examine well crafted modern theories, they include- from the beginning- cases that would falsify these theories. That is quite different from accidental observations that appear to invalidate some theory. Those need to be evaluated very carefully.
I'd like to explore this in more detail later; for now I'll merely note that whatever 'falsify' is, it has essentially no value when it comes to actually doing (modern) science ...

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Post by Chris Peterson » Sun Oct 26, 2008 11:46 pm

Nereid wrote:I'm pretty sure they don't ... nor were they intended to!
Okay, I guess I misunderstood your point. Some of these posts have gotten long and complex!
But how do you decide - ahead of time - what constitutes a "reasonable conclusion"? And how do you measure "strength" (of evidence)?
I'd just say it's part of crafting a good theory. Of course, it's not always simple. In general, it starts by stating specifically what a theory predicts. If that is done carefully, a failure of that prediction may absolutely falsify the theory. Taking Newton's law of gravitation again, it would not be a good prediction to state, in the case of Uranus, that the theory "predicts the planet will follow such and such a path". A good prediction would state that "the planet will follow such and such a path in the absence of unidentified gravitational (or other) forces". This establishes, from the beginning, a reasonable limitation. It recognizes that the failure to follow the predicted path cannot be taken as absolute falsifiability.

Strength of evidence is subjective. Theories are usually considered well supported when there are multiple, independent lines of evidence. If all the evidence is constructed like a chain, that's not so good.
How long would "long enough" have been? 1850? 1900? 2050?
The longer we looked without finding another gravitational influence, the less confident we would be in Newton. But we'd never know for sure, because the failure of Uranus to follow the expected path is not grounds for falsification. A better test needs to be used.
Another aspect: perhaps Uranus is (was) "an anomaly"? Everything else moved just as Newton ordered, both within the solar system and beyond. Should the textbooks have then said "Newton's universal law of gravitation (except for Uranus)"?
If I wrote the textbook, it would state that Uranus's path deviates very slightly from what we expect. This could reflect a flaw in the theory, or it could reflect the presence of an unseen planet. I would note that if we could not see Saturn, we would notice a very similar deviation in the orbit of Jupiter, and it was therefore more reasonable to assume an unseen planet than a broken theory, given that Newton is supported experimentally in ways unrelated to the motion of planets.
what do you mean by "although that had largely already been done"? AFAIK (as far as I know) the anomalous advance of the perihelion of Mercury was the only well-established observational or experimental result that 'falsified' (to be anachronistic) Newton, before publication of GR
You may be right. I have it in my mind that the two happened quite close, but I haven't looked at this particular science history for a long time.
in terms of content, GR couldn't be more different than Newtonian gravity!
Which fits nicely with my earlier observation (bit of personal philosophy, actually) that reality and theory are not connected. We have two very different mathematical treatments that match the same physical observations (keeping those observations inside their area of applicability, of course). So which is "real"?
But doesn't that raise rather knotty questions? Such as "what constitutes misinterpretation of a theory"? and "to what extent can the 'conditions of falsifiability' be defined beforehand"?
Good theories do a good job of defining the conditions of falsifiability. Just because it can be hard doesn't mean it can't be done.
The point is, how can we tell - today - what the (future) status of 'the Pioneer anomaly' is?
We can't. All we can do is recognize that we have an observation that hasn't yet been reduced to a single explanation, and which therefore can't be used to falsify any theory. It is an observation we need to study closer in order to use effectively.
...for now I'll merely note that whatever 'falsify' is, it has essentially no value when it comes to actually doing (modern) science ...
I thought that's the point you were trying to make in your earlier post, but that you then said you weren't trying to make. I'm confused. But regardless, I disagree strongly with this position. Theories (in all areas of science) are soundly falsified every day, with enough vigor that there is really no controversy about it. It has become quite common in science papers for the authors to explicitly define conditions of falsifiability. I think this is more applicable to the actual practice of science today than ever before.
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Post by apodman » Mon Oct 27, 2008 3:59 am

Pardon me, I need to clear my simple mind.

"apodman's simplified world of Scientific Theories
including theories in the subject of Astrophysical Cosmology"

---

Facts are ideas that are true.

We start with two kinds of Facts:

Facts of Observation - self-evident facts; visual facts requiring no interpretation; facts whose acceptance requires no validation.

Facts of Explanation - facts that generalize Facts of Observation; facts that describe unseen mechanisms manifested in Facts of Observation; "Laws of Nature"; facts whose acceptance requires validation.

---

Scientific Theories are attempts to narrow possibilities into Facts of Explanation.

We start with three aspects of Scientific Theories:

Competing Theories - hypotheses; tend to benefit more from falsifiability tests.

Established Theories - models; have already been questioned and tested to a degree; tend to benefit less from falsifiability tests; tend to be suited to improvement by more accurately defining a theory's limits.

Incomplete Theories - ideas; need other ideas to make a complete Scientific Theory.

---

Scientific Theories exhibit a mix of the aspects outlined above. A theory may be Established along much of its explanation, undecided among Competing choices in other parts, and have Incomplete sections. These parts might move around, change, and go through a progression over the life cycle of the theory.

To criticize, question, test, analyze, understand, support or cast doubt upon with evidence, accept, or reject a Scientific Theory, first see what aspects apply to the segment in question and treat the segment accordingly. If the state of the Scientific Theory does not match the logic of the approach, analysis will be difficult and fail to result in a coherent argument.

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Post by emc » Mon Oct 27, 2008 1:03 pm

Hi apodman and Nereid,

I don’t have a lot of time right now but wanted you to know I am trying to hang in there with this exciting, fun and interesting thread. I am posting this quick reply and hope to address more soon.

I am not acting when I present myself as the “humble layman”. MOF I had to look up ‘verisimilitude’ to make sure I understood what apodman said.

I just skimmed what I could in the internet about string theory… this is what I gleaned so far… Sting theory is a branch of theoretical physics centered on objects called strings. Blah, blah blah and adds a fifth dimension to GR (but it doesn’t state which member of the pop rock group is added) blah blah blah a specific “string” of string theory postulates twenty six dimensions… whoa! System overload… cannot compute… danger Will Robinson! Steady… steaaaady… look at APOD and meditate… steady… recovery complete! …Whew! …So string theory states that the universe is made up of sub-atomic vibrating strings. Maybe that explains why I love music so much. …My head hurts.

One of my favorite jokes in the electronics industry in regard to magic… If an integrated circuit (IC) or capacitor or any component explodes or fails in a short circuit it is commonly referred to as “letting the magic smoke out”.

I gotta go to work now.
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Post by Chris Peterson » Mon Oct 27, 2008 2:48 pm

emc wrote:I just skimmed what I could in the internet about string theory… this is what I gleaned so far…
String theory does provide a nice example in the context of this conversation. It is bad theory. In fact, it may not be theory in the scientific sense at all, given that nobody has really come up with much in the way of physical evidence to corroborate it, or observations that could be used to falsify it. In addition, the term "string theory" is a blanket for dozens of independent or nearly independent mathematical models.

None of this means that there is anything wrong with investigating string theory. In the long run it may be a very fruitful avenue of research. But it would be foolish to place it on a even footing with something like the standard cosmological model, or black hole theory, or stellar process theory. The latter are well developed, well corroborated, and testable. The former is a set of mathematical models that seem elegant and attractive, but so far have no tested or observed connection to the Universe. Unfortunately, it is common in the non-scientific press for theories to be described as if one were as good as another.
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Post by Nereid » Mon Oct 27, 2008 4:04 pm

apodman wrote:
Philosophy of Science

Karl Popper contended that the central question in the philosophy of science was distinguishing science from non-science. Early attempts by the logical positivists grounded science in observation while non-science (e.g. metaphysics) was non-observational and hence nonsense. Popper claimed that the central feature of science was that science aims at falsifiable claims (i.e. claims that can be proven false, at least in principle). No single unified account of the difference between science and non-science has been widely accepted by philosophers, and some regard the problem as unsolvable or uninteresting.
Karl Popper

Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive: it shows the theory, from which the implication is derived, to be false. Popper's account of the logical asymmetry between verification and falsifiability lies at the heart of his philosophy of science. It also inspired him to take falsifiability as his criterion of demarcation between what is and is not genuinely scientific: a theory should be considered scientific if and only if it is falsifiable.
Popperian Cosmology

Popperian cosmology also includes Karl Popper's theory of objective epistemology, also known as his theory of falsifiability.
---

(not to be confused with John Popper)
Bumping this as it's pertinent to some more recent posts.

Note the clarity of the role of falsification: "a single counterexample is logically decisive: it shows the theory, from which the implication is derived, to be false".

Snippets don't do justice to some of the actual subtleties of Popperian falsificationism (the quote is 'naive falsificationism', which patently does not describe what scientists do), but even with all kinds of bells and whistles (e.g. theories are most certainly not created equal - there's a definite hierarchy; even with quite unambiguous counterexamples ('fatal' counterexamples perhaps), 'good' theories are not abandoned until something better comes along), falsificationism is awkward, backward-looking, and (above all) lacks predictive power.

However, the last part ("a theory should be considered scientific if and only if it is falsifiable") is quite useful ... as long as 'theory' is clearly defined. Well, maybe; Popper certainly didn't solve the demarcation problem with falsificationism! :shock:

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Post by Nereid » Mon Oct 27, 2008 4:26 pm

Another older post ...
apodman wrote:
Nereid wrote:... perceptions of modern astrophysics and cosmology as science are quite interesting to me.
This concept is out of line, I think, with my not seeing belief as pertinent to fact.

I mean that astrophysics and cosmology, strictly speaking, are science, and that "perception" doesn't enter into it.

Maybe that's just my scientific prejudice talking, but I can't see it any other way.

If anybody here sees astrophysics and cosmology as non-science (or if anybody here knows and can quantify the views of those who do), please tell me about those views (what astrophysics and cosmology are, not what they aren't) so I can better understand the nature of Nereid's question.
It's a big internet, and it's very easy to set up a website!

A few hours searching will uncover an astonishing range of 'alternative' views, some of which are quite explicit in their claims that cosmology cannot be science, by definition.

More common however is the claim that modern astrophysics and cosmology is unscientific - i.e. what the pros actually do is not science, but that it is possible to do astrophysics and/or cosmology in a scientific manner (and you'll find great amounts of material on what, in these alternative views, the doing of 'real' astrophysics would entail).

For example: 'if you can't do a controlled experiment on it in your lab, it's not science' (that's an oversimplification of course) - so science goes no further than Voyager 1 and 2, the Earth below the mantle is beyond (today's) science, and so on.

Another group of alternatives might be termed 'neo-geocentrism' (crudely, the Earth is at the centre of the universe, by definition; astrophysics as science must start with that).

Does that help to show that there are different perceptions of astrophysics and cosmology, as science?

(FWIW one alternative has already been mentioned, briefly, in this thread).
Maybe I'm confused, too, about something similar to the two uses of "science" (the facts vs. the pursuit). Is it the methods, goals, and direction of modern cosmology that someone might find unscientific, or the current popular conclusions of modern cosmology (e.g., Big Bang or cold non-baryonic dark matter) that someone might find unscientific?

[...]
You'll find both, and sometimes all scrambled together.

The latter is, in principle, pretty easy to address: once you have agreement on the methods, the conclusions follow (e.g. black holes, CDM).

However, in my experience, strong expressions about the latter are, when you dig deep, nearly always founded on quite extraordinary views on the nature of astrophysics and cosmology (as science), though often those amazing differences are anything but explicit.

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