Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site uwmacc.UUCP Path: utzoo!watmath!clyde!bonnie!akgua!sdcsvax!dcdwest!ittvax!decvax!genrad!mit-eddie!godot!harvard!seismo!uwvax!uwmacc!dubois From: dubois@uwmacc.UUCP (Paul DuBois) Newsgroups: net.origins Subject: Re: Integrated Circuits. Part II. Message-ID: <585@uwmacc.UUCP> Date: Wed, 19-Dec-84 11:34:36 EST Article-I.D.: uwmacc.585 Posted: Wed Dec 19 11:34:36 1984 Date-Received: Sun, 23-Dec-84 01:40:30 EST References: <502@uwmacc.UUCP> <871@utastro.UUCP> Organization: UW-Madison Primate Center Lines: 206 > [Bill Jefferys] > At the end of a very long article, Paul DuBois says of my article: >>Well, anyway. Bill referred to overall design, but mentioned only >>the retina and the blind spot specifically. Perhaps he would like >>to restate his case, so I will leave off here. > Thank you, Paul. I wanted to concentrate only on these issues because > I believe they can be treated in isolation from the multitude of other > issues you raise. I had originally said: >>> Pray tell, if we are at the pinnacle of Creation, >>> how come the Creator got it right with the octopus and then stuck us >>> with a second-rate design? > From this, Paul derived what he thought was my position, to wit: >>(b) if humans are the pinnacle of creation, there should be no >> sensory function which a human performs more poorly than any >> other created organism. (last sentence of second excerpt) > This is not the same as the position I stated in my article, nor do I > agree with it. For the record, let me stipulate that I recognize that > a creator would take into account the needs of different organisms and > design eyes which were appropriate to the ecological niche occupied by > each organism. I am quite aware of the need for engineers to make design > trade-offs. That is not an issue. Therefore, most of Paul's article > (which counters point [b] above) is not relevant to my article. The obvious implication from the statement that the octopus has the right design while that of humans is second rate is that humans (if they are the pinnacle of creation) ought to have a retinal design at least as good as that of the octopus. The extension to any sensory system is equally obvious; restriction of such a claim to the design of the retina is data-sifting. Hence, I claim that (b) is in fact Bill's position whether acknowledged or not, unless the original remark is withdrawn. >>I find it curious that evolutionists continually raise the point >>about our inability to predict, *a priori*, any limits on the way in >>which a creator would create - and then go ahead and make their own >>suppositions. > On the contrary, whenever an obvious "prediction" is pointed out that > is not observed in fact, Creationists can think of a "reason" why > the "prediction" should be ignored. It is Creationism that is > malleable in this regard, not evolution. That Bill even makes such a "prediction" (i.e., that if humans are the pinnacle of creation, we should not be stuck with a second-rate design) reinforces the conclusion that (b) is in fact his actual position. But I wonder if speculation about relative superiority of eyes isn't fruitless. Whether the human eye is inferior or superior is irrelevant to the question of man as the pinnacle of creation without the additional assumption that sensory capability is a metric of the worth of man. I at least find this a doubtful proposition. On to other things... > My point is rather simpler. The general design of the cephalopod (e.g., > octopus) and vertebrate (e.g., human) eye is the same. The major > structural difference is the design of the retina, which in the > cephalopod may be said to be in "normal" position, and in the > vertebrate in "inverted" position. All other things being equal, > I claim that the cephalopod design is superior to the vertebrate > design since the latter has a "blind spot". I claimed, and demonstrated, that the apparent superiority of the cephalopod retina is illusory since no functional deficit results from possession of a blind spot. Also, as I pointed out, all other things are *not* equal. It may be objected (because Bill specifically stated his discussion to be limited to the design of the retina only) that I say this in an attempt to broaden the domain of consideration by an unreasonable degree. But I showed that this *must* be done. A retina is useless in isolation; indeed, to even begin to investigate Bill's claim one needs to consider other factors such as stereopsis and mobility of the organism. I would go so far as to state that the (erroneous) conclusion that the blind spot is a design fault results *precisely* from a failure to consider the other factors. I'm aware that I appear to be arguing a ridiculous thing, i.e., that a defect is not a defect. But that's exactly the point: you can't tell whether a thing is a defect unless you examine whether it *is* or *not*. > I can think of only a few ways to counter this simple observation. > First, it may be claimed that God knows best, and we are not to question > His decisions. I reject this. I hope that I am not misreading Paul's > article, but it seems that he accepts this as a legitimate position. > It is obvious to me that an argument of this kind has no place in > science. It's a misreading. Actually, I said it was not my position: "If it is true that creationists take this position as I have stated it [that we can't ask questions], and I think it may be reasonably maintained that some do, then indeed a self-defeating position has been taken, at least in the absence of proof that we shall *never* understand the function of such complexities." Needless to say, such proof may be difficult to supply in most cases. > Secondly it may be argued that the two designs are equally good, so > that it doesn't matter which design is picked. Paul addresses this > issue: >>[long discussion why blind spot is irrelevant, omitted -- pd] >>[Bill concludes: ] > I would say that these points argue for *evolution*, not creation. > Paul has shown how "kludging around" with other aspects of the > human visual system are able to compensate for the design flaw, > which is precisely the point I made more generally. This conclusion is valid given the prior assumption of a design flaw. Which is precisely the question! "Kludging" must be assumed. > Paul mentioned a third argument that I had not thought of, namely, > that the human eye perhaps had degenerated from an originally more > perfect design: >>If a more positive statement were desirable, one might infer a >>principle of genetic deterioration in consonance with the tenet of >>physical degeneration that seems to be a part of the standard >>creationist model, citing as specific evidence the deleterious or >>lethal nature of many mutations. ... > I find this an amazing hypothesis to come from a Creationist. To go > *from* a normal cephalopod retina *to* an inverted vertebrate one > would seem to be much more difficult than evolving either from > simpler forms, yet Creationists are always saying that even the latter > kind of transition is impossible. I was surprised to find Bill attributing such a thing to me at first, but after re-reading my article it appears to be inferrable from it. The above isn't what I meant, so I shall explain further. I was thinking of apparent design flaws in general, considering that *some* apparent design flaws could be explained on the basis of degeneration, such as the finding that pig insulin works better in guinea pig that guinea pig insulin. This would (I think) be consistent with the hypothesis of degenerative mutations. I did not consider the issue of retinal characteristics to fall under this explanation, since I discussed that issue from another viewpoint (i.e., that it's not a design flaw at all). Anyway, thank you, Bill, for pointing this out. I suppose this obscurity may have confused other readers as well. > Finally, it may be argued that there is a genuine design trade-off. > That is, perhaps there is something about the inverted retina that > makes an important trait such as color vision possible. Paul also > alludes to this: >>Bill has discussed one aspect of visual function (ther retinal blind >>spot), concluding that the evidence implies inferiority of the human >>eye. My comments in the previous section lead to a different >>conclusion, but I still have to ask in a more general sense how the >>human eye is "clearly inferior" to the octopus eye. Bill mentions >>the overall design ("design" being a poor word given the thrust of >>his argument), but his comments only discussed the design of the >>retina. This is certainly artificial; a retina is useless by >>itself. Let us consider general ocular superiority. This would >>include consideration of such things as the following: >> >> o accommodative ability >> o chromatic and spherical aberration of the lens >> o pupillary reflex >> o vergence and version control for binocular functioning >> o stereopsis >> o resolution of extraocular muscle nervous innervation >> o night/day visual capacity, pattern of neural convergence >> of the photoreceptors onto the ganglia (already discussed) >> o color vision >> o rod/cone demography >> o response to foreign objects (i.e., defense against) >> o facilities for distance perception > Of this list, only color vision and rod/cone demography, which involve > the retina, might be endangered by a different retinal design. The other > aspects could equally well exist in conjunction with either the > cephalopod or the vertebrate design. To make a case for a design trade-off > requiring an inverted retina, one would have to provide evidence to show > that a normal retina cannot support these aspects of human sight. No > such case has been made, and I would argue that it is unlikely that > any such case can be made. It is even more unlikely that I shall try to make such a case, because the argument here is beside the point. I suppose both designs *might* support any visual feature listed above. I was more concerned with what each visual system *actually* does. -- Paul DuBois {allegra,ihnp4,seismo}!uwvax!uwmacc!dubois "I will sing unto the Lord as long as I live: I will sing praise to my God while I have my being." Psalm 104:33