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Solfe
2010-Jul-29, 02:15 AM
I took some pictures of a double rainbow. Is it normal for the outer rainbow to be reversed?

http://pretendertothepower.com/assets/images/rainbow1.jpg (31 kb)
http://pretendertothepower.com/assets/images/rainbow2.jpg (33 kb)
http://pretendertothepower.com/assets/images/rainbow3.jpg (41 kb)

Just wondering,

Solfe

Nick Theodorakis
2010-Jul-29, 02:52 AM
Yes, that's normal.

Nick

baric
2010-Jul-29, 03:07 AM
What does it mean??

LotusExcelle
2010-Jul-29, 03:18 AM
Here is a great resource:
http://www.atoptics.co.uk/

And here is the entry on doubles:
http://www.atoptics.co.uk/rainbows/sec.htm

korjik
2010-Jul-29, 03:33 AM
What does it mean??

Means it bounced off the inside of the raindrop twice instead of once.

George
2010-Jul-29, 03:51 AM
It helps to use polaroid glasses to see the fainter second rainbow. Be sure to rotate them to obtain best alignment.

GeorgeLeRoyTirebiter
2010-Jul-29, 05:25 AM
Means it bounced off the inside of the raindrop twice instead of once.

I think baric was actually referencing a recently popular YouTube video in which a man is overjoyed by the sight of a double rainbow.

If you like, you can enjoy the Gregory Brothers' musical version of said video:
http://www.youtube.com/watch?v=MX0D4oZwCsA

Ken G
2010-Jul-29, 04:02 PM
And the secondary is reversed because it bounces a second time, and bounces are always interpreted as reversing side to side-- just like in a mirror.

Perikles
2010-Jul-29, 04:45 PM
I have even seen a third rainbow during a spectacular storm, where of course the colours are in the same order as the first one. BTW, even Aristotle noticed this reversal in his treatise on rainbows, but his explanation for the phenomen leaves a lot to be desired (=complete nonsense). He also claimed the rainbow only had 3 colours.

baric
2010-Jul-29, 05:58 PM
I think baric was actually referencing a recently popular YouTube video in which a man is overjoyed by the sight of a double rainbow.

If you like, you can enjoy the Gregory Brothers' musical version of said video:
http://www.youtube.com/watch?v=MX0D4oZwCsA

You have to watch the original first!

http://www.youtube.com/watch?v=OQSNhk5ICTI

This man is so awestruck by the sight of a double rainbow that he is reduced to tears and wondering "what does it mean?"

It's very touching, funny and even a little scary, all at the same time -- depending on your perspective.

LotusExcelle
2010-Jul-29, 06:19 PM
I took the video to 'mean' that he was either exhausted, dehydrated, high, or drunk.

grant hutchison
2010-Jul-29, 06:31 PM
I have even seen a third rainbow during a spectacular storm, where of course the colours are in the same order as the first one.That's a surprise. The tertiary bow is very faint, about the same diameter as the primary, and would appear in the sunward direction, so that its inside and outside colours would appear reversed compared to the primary.

I wonder if your third rainbow was a result of reflection from water. If there's a body of flat, illuminated water between you and the falling rain, the sun reflects off the water and generates an indirect primary (and secondary) bow. These touch the horizon at the same points as the direct primary and secondary bows, but rise higher in the sky. With a fairly high sun reflecting off a small patch of water, one can then see a fragment of indirect primary hanging above the direct primary and secondary.

ETA: Here (http://www.atoptics.co.uk/rainbows/reflect.htm) is a page containing a diagram of these reflection rainbows. I often see a quite spectacular display similar to to the photograph, with the lower parts of the reflection rainbow(s) standing up from the estuary outside my house, like a pair of rainbow pillars built at one end of the conventional display. But I've also once seen a display that featured only the upper curve of the indirect primary bow, which seemed to hover in the air above the standard double rainbow. (At the time, I was caught in rain in an area of moorland dotted with many small bodies of water.)

Grant Hutchison

Jens
2010-Jul-30, 05:31 AM
He also claimed the rainbow only had 3 colours.

How many colors are there?

Perikles
2010-Jul-30, 08:55 AM
That's a surprise. The tertiary bow is very faint, about the same diameter as the primary, and would appear in the sunward direction, so that its inside and outside colours would appear reversed compared to the primary.This is worrying, it was inland with no water, and the three rainbows were concentric, about equal angular distance apart. From your description, it doesn't sound plausible. The primary one was of a brightness I have only ever seen on that occasion.


How many colors are there?Obviously three. Magister dixit. :lol:

Jens
2010-Jul-30, 09:32 AM
Obviously three. Magister dixit. :lol:

The real answer is infinite, though, isn't it?

Perikles
2010-Jul-30, 09:37 AM
The real answer is infinite, though, isn't it?Interesting question. If there is a finite number of photons, then not quite infinite. Hmmm.

grant hutchison
2010-Jul-30, 11:00 AM
This is worrying, it was inland with no water, and the three rainbows were concentric, about equal angular distance apart. From your description, it doesn't sound plausible. The primary one was of a brightness I have only ever seen on that occasion.Odd.
For three concentric bows all I could offer would be a so-called supernumerary bow: a diffraction phenomenon that occurs on the inner curve of the primary rainbow and on the outer curve of the secondary. The primary supernumerary is very common if you go looking for it, but it rarely seems to catch people's eyes unless the primary is very bright, which makes the supernumerary colours stand out brightly, too.

But the supernumeraries are stacked curves of repeating pastel colours, lying pretty close to the "parent" bow. That doesn't sound at all like what you describe.

Do you have a photograph, at all?

Grant Hutchison

Perikles
2010-Jul-30, 11:14 AM
Do you have a photograph, at all?I'm afraid not - it caught me by surprise after a thunderstorm. Judging by my failed efforts to photograph rainbows, I very much doubt whether the very faint third bow would have been visible on a photo anyway. It was quite some time ago, but I remember it clearly.

Swift
2010-Jul-30, 01:12 PM
Originally Posted by Jens
The real answer is infinite, though, isn't it?Interesting question. If there is a finite number of photons, then not quite infinite. Hmmm.
It wouldn't be dependent upon the number of photons, whether finite or infinite. It would depend on the wavelengths of the photons and how much the human eye can distinguish one wavelength from another.

For example, according to this NASA website (http://eosweb.larc.nasa.gov/EDDOCS/Wavelengths_for_Colors.html) blue has a wavelength around 475 nm and green around 510 nm. Or, you could say blue is from 460 to 490 nm (for example). I'm sure you could sub-divide this further and say blue is 480 to 485, blue-green is 485 to 493, etc., etc. But at some point, your eye and brain just won't see a difference. At an extreme, saying 485.473 nm is a different color from 485.474 nm is probably unreasonable.

What I don't know is what is the wavelength resolution of the human eye.

Perikles
2010-Jul-30, 01:29 PM
What I don't know is what is the wavelength resolution of the human eye.I remember reading somewhere the eye could distiguish around 10,000 different colours, or that sort of magnitude. Sounds hard to believe.

Swift
2010-Jul-30, 01:41 PM
This technical guide from Adobe (http://dba.med.sc.edu/price/irf/Adobe_tg/color/light.html) says the same thing. Given the visible range is about 380 to 780 nm, that would
imply a wavelength resolution of 0.04 nm.

The wikipedia page about color vision (http://en.wikipedia.org/wiki/Color_vision) gives a rather different answer.

Sufficient differences in frequency give rise to a difference in perceived hue; the just noticeable difference in wavelength varies from about 1 nm in the blue-green and yellow wavelengths, to 10 nm and more in the red and blue. Though the eye can distinguish up to a few hundred hues, when those pure spectral colors are mixed together or diluted with white light, the number of distinguishable chromaticities can be quite high.



This webpage from the University of Cincinnati (http://www.rwc.uc.edu/Koehler/biophys/6d.html) has more details about how the eye works, but doesn't address that particular question.

The cone cells of the human eye are sensitive to 3 wavelength ranges which the eye interprets as blue (narrow, with a peak near 419 nm), green (broader, with a peak near 531 nm) and red (also broad, with a peak near 558 nm, which is actually more like yellow!): <graph not reproduced here>

...

(from Vos, J. J. & Walraven, P. L.). All of the colors which your mind perceives are constructed from combinations of relative intensities of these three "wavelengths": red, green and blue are the only "signals" your brain receives from your eyes.

George
2010-Jul-30, 03:34 PM
This site (http://www.visualexpert.com/FAQ/Part2/cfaqPart2.html) suggest over 1 million colors (varying hue, saturation & brightness), possibly up to 7 million colors.

grant hutchison
2010-Jul-30, 04:24 PM
In this discussion, it's worth recalling that a rainbow doesn't cover the whole of colour space: any given rainbow will cover just a fairly narrow band of desaturated spectral colours, which will be projected on to a fairly small area of the retina.

We can distinguish more colours than the spectral colours.
We're less good at distinguishing spectral colours when they're desaturated.
We might be able to distinguish more colours in any given rainbow if we could see them spread out more, especially if the colours were presented with distinct edges, as is commonly done with colour chips when testing colour vision.
So I suspect the problem isn't soluble in a useful or informative way by thinking about the number of different colour distinctions a human eye can make under careful test conditions.

What Aristotle presumably meant was that the rainbow spanned just three regions of colour space to which he would assign distinct colour names, albeit with more or less vague transitional zones between. The colour language of the Ancient Greeks is notoriously strange to modern Europeans, who divide colour space differently, and it's difficult to work out exactly what they meant by their various colour words.

Grant Hutchison

Grey
2010-Jul-30, 04:27 PM
This site (http://www.visualexpert.com/FAQ/Part2/cfaqPart2.html) suggest over 1 million colors (varying hue, saturation & brightness), possibly up to 7 million colors.Note that this is not necessarily in conflict with the Wikipedia page that Swift quoted. Note that there they were talking about being able to distinguish between hundreds of different hues, and then talked about a larger number of "distinguishable chromaticities", which presumably corresponds to the additional variations in saturation and brilliance discussed in George's link.

Ken G
2010-Jul-30, 04:43 PM
What Aristotle presumably meant was that the rainbow spanned just three regions of colour space to which he would assign distinct colour names, albeit with more or less vague transitional zones between. The colour language of the Ancient Greeks is notoriously strange to modern Europeans, who divide colour space differently, and it's difficult to work out exactly what they meant by their various colour words.Splendidly navigated nuances. Poor Aristotle, talking to us across two millennia of culture shock, and expected to be taken literally in everything he says! Is it not strange how quick we can be to dismiss Aristotle as a kind of complete nincompoop, despite being one of the most accomplished minds of his era? Is that just because he's a philosopher, so "fair game" for judging a cretin?

So much of Greek writing has been lost, that I sometimes wonder if perhaps they discovered some truth that we have yet to rediscover even to this very day. Indeed, I've argued on other threads that Zeno's paradoxes harbor glimpses of such truths, though it's not clear how close is the connection between his intent at the time, and the modern view of phenomena like the "quantum Zeno effect." Not to go OT to the rainbow question, it's just a musing on how glibly we dismiss ideas that don't fit our current mindset.

Perikles
2010-Jul-30, 05:34 PM
Splendidly navigated nuances. Poor Aristotle, talking to us across two millennia of culture shock, and expected to be taken literally in everything he says! Is it not strange how quick we can be to dismiss Aristotle as a kind of complete nincompoop, despite being one of the most accomplished minds of his era? Is that just because he's a philosopher, so "fair game" for judging a cretin?.I for one am not dismissing him like that, he was obviously the keenest of observers of physical phenomena with an acute attention to detail. Where he fails is in my mind is too much confidence in his own ability to explain a physical phenomenon, and his writings often smack of sheer bluff. I quote here from his Meteorologica where it seems he satisfies himself with an explanation of the rainbow: (my bolding)


Meteorologica 374b27 - 375b15 (excerpts)

The reason is clearly that, just as our vision when reflected through an angle and so weakoned makes a dark colour still darker, so also it makes white appear less white and approach nearer to black. Whe the sight is fairly strong the colour changes to red, when it is less strong to green, and when it is weaker still to blue. There is no further change in colour, the complete process consisting , like most others, of three stages; any further stage is imperceptible. This is why the rainbow is three-coloured, and why, when there are two of them, each is three-coloured, but the colours are in the reverse order of each. In the primary rainbow the outermost rainbow is red. For the vision is reflected most strongly on to the sun from the largest circumference, and the outermost band is the largest.... The yellow colour that appears in the rainbow is due to contrast of two others; for red in contrast to geen appears light.... Three or more rainbows are never seen, because even the second is dimmer than the first, and so the third reflection is altogether too feeble to reach the sun.

The whole passage is baffling to me, and notice he assumes that sight is rays emanating from the eye, not the other way round. Does he really satisfy himself with this explanation, or is he bluffing? How can he admit to yellow being there, but not? (But I do love the Greek word for rainbow: Iris)

Ken G
2010-Jul-30, 05:53 PM
I for one am not dismissing him like that, he was obviously the keenest of observers of physical phenomena with an acute attention to detail. Where he fails is in my mind is too much confidence in his own ability to explain a physical phenomenon, and his writings often smack of sheer bluff.You have a point. Perhaps he at times felt like the Dad in Calvin and Hobbes-- too much pressure to always have the answer. Or maybe it was just the Greek style to put the hypothesis out there and let it stand or fall, with little effort to confess the uncertainties! He was certainly wrong on a lot of points, but that didn't make him a fool, it made him a step in the process. (I don't say you are calling him a fool-- if I felt you were too quick to judge him that way, perhaps it was I who was too quick to judge.)

I quote here from his Meteorologica where it seems he satisfies himself with an explanation of the rainbow: (my bolding)He certainly has a lot wrong there-- he seems to confuse color with intensity. But as Grant points out, there are interconnections there. As for reversing the direction of the flow of light, that is not as large a mistake as one might think-- if the speed of light is effectively infinite, its direction works just as well either way (the principle of "reciprocity").

Perikles
2010-Jul-30, 06:04 PM
As for reversing the direction of the flow of light, that is not as large a mistake as one might think-- if the speed of light is effectively infinite, its direction works just as well either way (the principle of "reciprocity").I have often pondered this reversal, and decided that from the ancient Greek perspective it is perfectly understandable. I can't think offhand of a physical process which they could observe which would demonstrate otherwise, and indeed the effect, say, of a look from an enemy in battle, (or the look from a wife when she thinks the husband has had a little too much to drink in company) does indeed clearly suggest the wrong direction of light.

Gillianren
2010-Jul-30, 06:57 PM
Do remember that it was the philosophical model at the time that the idea was more important than the reality. Aristotle believed horses had a different number of teeth than they actually do, because actually bothering to count their teeth was not worth the time of a true philosopher. Aristotle's philosophy is a matter of debate, as all philosophy is. His science actually is bad, because he wasn't actually a scientist, for all the world has long considered him one.

grant hutchison
2010-Jul-30, 07:14 PM
It occurs to me that I've previously discussed with Perikles the suggestion that the Ancient Greeks were colour-blind. At the time I could only offer a secondary source for this idea.
I've since traced it back to no less a figure than William Gladstone (a Prime Minister of Britain) who was a considerable authority on Homer. He seems to have been the first (but not the last) to fret about the Greek's colour sense, which he discussed in an appendix to his huge monograph, Studies on Homer and the Homeric Age.
Since Gladstone's time, we've taken more interest in the many ways in which non-European cultures parse colour space, and it seems to be generally accepted that Homer's writings, and the Greek colour names generally, simply reflect a different way of thinking about colour, rather than a different perception of colour.

Grant Hutchison

Gillianren
2010-Jul-30, 07:56 PM
We also have Greek statues which show signs of having been painted--in colours which aren't that different from what we might use today.

ETA--Wait, are you calling the Greeks "non-European"? "Europe" is a Greek name!

George
2010-Jul-30, 08:11 PM
[ Here (http://www.princeton.edu/~classics/conferences/2008/ancientphil/documents/ButlerColor.pdf) is a very comprehensive peek (Friday's oxymoron ;)) at Artistotle's color view. ]

George
2010-Jul-30, 08:17 PM
Aristotle's philosophy is a matter of debate, as all philosophy is. His science actually is bad, because he wasn't actually a scientist, for all the world has long considered him one. He was human. He thought like a modern scientist at times but often was able to do just fine in his and other's minds, which probably minimized the interest in experimentation, but, apparently, he did some experiments.

I suppose the silver lining to his gross errors is that they contributed greatly to Galileo's not drinking all the various Kool-Aids the philosophers, and many theologians, required others to drink.

grant hutchison
2010-Jul-30, 08:23 PM
ETA--Wait, are you calling the Greeks "non-European"? "Europe" is a Greek name!No, I'm saying that in Gladstone's day, people didn't pay much attention to the naming of colour space by languages outside Europe, and it happens that most modern European languages parse colour space similarly. Now that we have experience of a larger number of languages from other language families, we've come to understand that there are many different ways to describe colour, and that has helped us look back at Ancient Greek with new understanding.

Grant Hutchison

Ken G
2010-Jul-30, 10:05 PM
And I wouldn't be surprised if the horse's teeth issue was similar. Which is easier to believe, that Greeks were colorblind, or can't count, or just had a different way of talking about what they were observing, and we're not always getting the message across the cultural divide? Or they may have made certain honest mistakes. The idea that just because they were philosophers, they didn't think they needed to try to actually observe the world, is highly inaccurate, and even a bit insulting to someone with that level of intelligence. Aristotle did have a healthy distrust of observations, because he understood experimental error (an important scientific topic) and the limitations of perception, and because he had an overarching desire to be able to conclude that the universe made logical sense, even to a fault (too bad he never read Douglas Adams). But he disagreed famously with his mentor Plato, as Plato thought the perfect forms preceded the physical objects we observe, but Aristotle felt the perfect forms were concepts we created out of what we observed. That way of thinking is pretty close to a foundation of modern scientific thinking. For this reason, some consider Aristotle to be the first scientist. Notwithstanding the fact that science has quite an excess of "fathers of", we can certainly say that Aristotle was the pre-eminent scientist of his day.

And not to go too far OT (OK, to go too far OT), some of Aristotle's ideas that might at first look seem a bit flaky actually find much more traction in modern science than you might recognize. Aristotle looked to "first causes" of phenomena, in addition to various detailed or incidental causes, because he felt that things happened for a reason. It rained because plants need rain, that sort of thing. It is easy to attribute teleological thinking like that to religious doctrines, and say it is anathema to good science, but that's not really true-- it all depends on how literally you take the teleology. Darwinian evolution is highly teleological, in that we end up with animals being the way they are because it is good for their survival to be that way. And to address the fine-tuning of the physical constants to allow life, many modern theoretical physicists turn to anthropic thinking-- our universe is selected from many because we select it by being here. That is not at all hard to turn into yet another teleological argument-- the universe is how it is because we need it to be that way.

It's funny how those naive, antiquated, foolish concepts that we have left so far behind have a way of coming back and biting us on the backside.

baric
2010-Jul-30, 10:20 PM
Let us not forget that many of the classical Greek works, including Aristotle's Meteorology, survived to the modern day only through the benefit of multiple translations.

Greek -> Arabic -> Latin -> English version quoted in this thread


I believe that the Arabic translators of the Green originals also translated through an intermediate language, although the details escape me now.

Ken G
2010-Jul-30, 10:36 PM
Good point-- I'd sure hate to have my forum posts translated three or four times, I shudder to think what would come out the other end of that process! (An improvement?)

baric
2010-Jul-30, 11:27 PM
Good point-- I'd sure hate to have my forum posts translated three or four times, I shudder to think what would come out the other end of that process! (An improvement?)

To Greek

Καλό σημείο - μάλλον θα νιώθω απαίσια να έχει δημοσιεύσεις στο φόρουμ μου μεταφραστεί τρεις ή τέσσερις φορές, ανατριχιάζω να σκεφτώ τι θα βγει το άλλο άκρο αυτής της διαδικασίας! (Η βελτίωση;)

Then to Arabic

نقطة جيدة -- أنا أكره من المؤكد ان يكون في المنتدى الخاص بي ترجمت إلى ثلاث أو أربع مرات ارتجاج الأول ، أن يفكر ما يخرج الطرف الآخر من هذه العملية! (أفضل؟)

Then to Italian (surrogate for Latin)

Buon punto - certamente odio essere nel mio forum sono stati tradotti in tre o quattro volte mi vengono i brividi, a pensare cị che viene fuori l'altra estremità del processo! (Meglio?)

and finally back to English

Good point - certainly hate to be in my forum have been translated into three or four times I shudder to think what comes out the other end of the process! (Better?)


wow.. I have to give google translate some credit. Most of that was preserved, although your IQ does look about 20 points lower! :P

Tobin Dax
2010-Jul-31, 12:54 AM
Good point-- I'd sure hate to have my forum posts translated three or four times, I shudder to think what would come out the other end of that process! (An improvement?)

The loss of a noun, apparently. Not an improvement, IMO. I have to disagree with baric, since I wouldn't be able to figure the first half of the sentence in the final translation back to English.

Ken G
2010-Jul-31, 05:32 AM
wow.. I have to give google translate some credit. Most of that was preserved, although your IQ does look about 20 points lower! To be honest, I did a very similar exercise myself, and when the results were disappointingly undemonstrative of my point, I didn't post it! (Though you actually got more garbled results than I did, Tobin Dax is right about that first part.) Apparently the translators have improved. But one should note, some translations could still completely butcher my point, as long as the inverse translation back to English de-butchered it. We'd have to ask someone who knows Greek or Arabic! Also, the translations of Aristotle did not sound like he had lost IQ, so that probably means that someone along the way re-boosted the translation to make it sound like it came from an agile speaker in the new language-- but at what cost to the meaning?

baric
2010-Jul-31, 06:11 AM
To be honest, I did a very similar exercise myself, and when the results were disappointingly undemonstrative of my point, I didn't post it!

omg, bad scientist! Bad, BAD SCIENTIST! Always go where the evidence leads you!

In fairness, we did lose a key noun in your short post. If a key noun were lost in every other sentence in a 20-page paper, it would be very difficult to parse. Nuances would be lost and there would be debates about your meaning in certain places.

But it's even worse for Aristotle. When the early Muslims were translating Greek works, they literally did not have words in their language for many of the concepts being discussed by the Greeks. As a result, they simply incorporated many Greek words directly into their language to compensate. You can imagine the difficulties of accurately translating works that are beyond your current technological knowledge.

mugaliens
2010-Jul-31, 07:39 AM
wow.. I have to give google translate some credit. Most of that was preserved, although your IQ does look about 20 points lower! :P

I'm convinced!

ETA: Of Google's translation capability.

Perikles
2010-Jul-31, 09:21 AM
Let us not forget that many of the classical Greek works, including Aristotle's Meteorology, survived to the modern day only through the benefit of multiple translations.

Greek -> Arabic -> Latin -> English version quoted in this thread.This is a truly surprising statement, since I am looking at the original Greek text of Meteorologica as I type, and giving an English translation directly from it. Behind me are quite a few texts of Aristotle: Metaphysics; Physics; Poetics; Rhetoric; etc., all in the original Greek.

It is perhaps worth mentioning that these texts do not seem to be well structured books, but more like lecture notes, with faulty structures, repetitions and the like. This makes the reading even more difficult than if they were well planned with a careful attention to train of thought.

Perikles
2010-Jul-31, 09:37 AM
It occurs to me that I've previously discussed with Perikles the suggestion that the Ancient Greeks were colour-blind. At the time I could only offer a secondary source for this idea.
I've since traced it back to no less a figure than William Gladstone (a Prime Minister of Britain) who was a considerable authority on Homer. He seems to have been the first (but not the last) to fret about the Greek's colour sense, which he discussed in an appendix to his huge monograph, Studies on Homer and the Homeric Age.
Since Gladstone's time, we've taken more interest in the many ways in which non-European cultures parse colour space, and it seems to be generally accepted that Homer's writings, and the Greek colour names generally, simply reflect a different way of thinking about colour, rather than a different perception of colour.
Yes, it all sounds rather familiar. I didn't know about Gladstone, and yes, a different way of thinking rather than a different physical perception. I mean, Aristotle asserts there are only three colours, but mentions yellow as a fourth one, which he was able to see. It is hard to see why he denies it is there.

Perikles
2010-Jul-31, 09:50 AM
The idea that just because they were philosophers, they didn't think they needed to try to actually observe the world, is highly inaccurate, and even a bit insulting to someone with that level of intelligence. .This is just a modern erroneous idea caused by the shift in meaning of the word 'philosopher'. Aristotle was an acute observer of all kinds of physical phenomena: I open Meteorologica at random and read - Water has sometimes burst out of the earth when there has been an earthquake; further - Earthquakes are rarer in islands further out to sea; and so on (Discussed in Meteorologica because he thought that winds cause earthquakes, but I won't bore you with the reasoning)

Perikles
2010-Jul-31, 10:01 AM
[ Here (http://www.princeton.edu/~classics/conferences/2008/ancientphil/documents/ButlerColor.pdf) is a very comprehensive peek (Friday's oxymoron ;)) at Artistotle's color view. ]Thanks for that - it even mentions the rainbow, without coming to any conclusion. I'm not sure whether the paper comes to any particular conclusion at all.

baric
2010-Jul-31, 02:41 PM
This is a truly surprising statement, since I am looking at the original Greek text of Meteorologica as I type, and giving an English translation directly from it. Behind me are quite a few texts of Aristotle: Metaphysics; Physics; Poetics; Rhetoric; etc., all in the original Greek.

I had suspected, Perikles, that you would be conversant in Greek! I know that some of the ancient works survived without translation but did not know which particular ones. So before I posted, I tried to do a little googling and found Aristotle's Meteorologica was mentioned as a translated work.

If the original Greek versions of those works are indeed still available, then my note on translation errors is unfounded.

Perikles
2010-Jul-31, 03:06 PM
If the original Greek versions of those works are indeed still available, then my note on translation errors is unfounded.Not quite unfounded, it was a good point. The original Greek is difficult to translate, and there is plenty of scope to distort the text even when translating directly from it. If the topic is covered only in one extant text, then the vocabulary specific to that text may have a nuance of meaning which you can't know about because you have no comparison text. It can be an area of dispute. (But the Meteorologica is relatively easy text)

Solfe
2010-Oct-06, 01:23 AM
Yes, I am raising a dead thread, but back to the original topic of double rainbows. I was very excited to see a double rainbow and get a passable picture, but this guy was way more excited about double rainbows:

http://www.youtube.com/watch?v=OQSNhk5ICTI

Perikles
2010-Oct-06, 09:09 AM
but this guy was way more excited about double rainbows: What was he on? It sounds like some serious altitude sickness. I love the philosophical question which was clearly too much for him: What does it mean?