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Atheism and Theism JJ Haldane - Common Sense Atheism

Atheism and Theism JJ Haldane - Common Sense Atheism

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Reply to <strong>Haldane</strong> 159<br />

4 Chicken <strong>and</strong> Egg<br />

Which came first, the chicken or the egg? I am here indebted to a witty<br />

discussion note by Roger Teichmann. 21 Since each chicken is hatched from<br />

an egg <strong>and</strong> every egg is laid by a chicken, it would appear that neither can<br />

come first. On the other h<strong>and</strong> since the durations of the generations of<br />

chickens have a lower bound (so the sequence is not like, say, . . . 1 /8, 1 /4, 1 /2,<br />

1, . . . ) <strong>and</strong> because life on earth has not existed for ever, it would appear that<br />

there would have to be a first egg or first chicken. The answer of course must<br />

be that ‘chicken’ is a vague term. We get the same appearance of contradiction<br />

with any vague term, as is exemplified by the so-called Sorites paradox. If<br />

a man with only a few hairs on his head (say 10) is bald, so also is a man with<br />

one more hair (say 11). Also if a man with n hairs on his head is bald so is<br />

a man with (n + 1) hairs. (One more hair does not make the difference<br />

between being bald <strong>and</strong> being not bald.) So from this we seem to be able to<br />

deduce that the hairiest head of hair that you’ve ever seen is that of a bald<br />

man. Much has been written on the Sorites paradox, <strong>and</strong> as far as I know<br />

there is still no agreed solution. The trouble comes from the vagueness of<br />

language, as with ‘bald’. Similarly ‘chicken’ is vague. There is no first chicken.<br />

Species evolve imperceptibly from earlier species. Unless, of course, some<br />

miraculous occurrence singled out a first chicken or a first egg.<br />

We should take ‘egg’ here in the sense of ‘ovum’. (The eggs we eat consist<br />

mostly of nutrient for the growing chicken foetus.) Wouldn’t there have to be<br />

a first ovum? Well, there might have been a first coming together of bits of<br />

DNA to form the first prototype of bisexual reproduction, <strong>and</strong> one of them<br />

might be regarded as proto-egg <strong>and</strong> proto-sperm.<br />

<strong>Haldane</strong> likes to stress the discontinuities: the reproductive from the nonreproductive,<br />

the organic from the non-organic, the conceptual from the<br />

non-conceptual. 22 These things arise by sequences of small jumps. Each jump<br />

may have a low probability, but evolutionary time is long compared with the time<br />

of human affairs. If a jump consisted simultaneously of millions of jumps<br />

its probability would be exceedingly low. However, a sequence of millions<br />

of small jumps filtered by natural selection can have a much higher probability.<br />

There is a problem about how the evolution of a complex organ, such as the<br />

eye, might have occurred. The answer lies in the opportunist character of evolution<br />

whereby something that gives one sort of advantage at one stage may<br />

lead to different advantages at later stages. <strong>Haldane</strong> might say that small jumps<br />

are still jumps. So they are, but the smallest jumps are a matter of chance<br />

comings together <strong>and</strong> chance mutations. But you shouldn’t be reading me on<br />

this. Read the biologists <strong>and</strong> make up your own mind whether you think that<br />

the naturalist story or the supernaturalist story is the more plausible.

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