[1] At one point Popper explicitly calls this "Paley's problem" (p. 345); but elsewhere in this same paper he refers to "Paley's and Darwin's problem" (p. 342), which is thus consistent with my designation of tex2html_wrap_inline1530 as "Darwin's Problem". I shall consistently use the latter name; partly because I have used Darwin's formulation, rather than Paley's, to introduce it; but mainly because there is a subtle difference between the problem as originally conceived by Paley, and as actually solved by Darwin. In my construction ( tex2html_wrap_inline1530 ), the (conjectured) truth of common descent is an explicit part of the problem situation; whereas, for Paley, the truth of common descent was neither a necessary part of (nor even particularly relevant to) the problem situation.

[2] To this extent, the title of Darwin's book, 
  The Origin of Species may be slightly misleading-it directs
  attention specifically at the phenomenon of speciation, rather
  than at the growth of adaptive complexity.  While speciation is
  certainly an important issue we can say nonetheless that it is of
  secondary importance compared to the question of adaptive complexity.
  Diversity of species as such would be of relatively little interest if
  all species were equally rudimentary; conversely, even if there were
  only one species which displayed adaptive complexity, this one species
  would be of overwhelming interest. This is not, of course, to argue
  that speciation and the growth of adaptive complexity are 
  independent phenomena, but 
  merely that I shall concentrate on the
[3] Attempts have, of course,
  been made to apply "Darwinian" theory to a vast range of domains; I
  use the "organismic" qualifier here simply to emphasise that I am
  talking about the application of Darwinism in its original context of
  the evolution of biological organisms. This usage is loosely related
  to the Organismic Evolution of
  Beurton (1981), and the Organismic
  Selection of Wright (1980).
[4] I find 
the latter term to be seriously confusing.  This is discussed 
at length in (McMullin 1992c).
[5] The common "S" prefixes in
  S-lineage and S-value are co-incidental, since they denote
  "similarity" and "selection" respectively;
  but since only S-lineages can have S-values, it is a convenient
  co-incidence; I did not intend it, but I am happy to allow it
[6] S-value is not even necessarily transitive. One
  could formulate S-lineages A, B, C, with properties such that
  all three distinct pairs would give rise to selection processes, where
  A would reliably displace B, B would reliably displace C, yet
  C would reliably displace A!
[7] This thesis is commonly expressed by saying that
  variation is "random"; but that term is very vague 
  and ambiguous.
[8] Admittedly, it is a moot point
  whether this is true of unicellular organisms;
  but I shall not pursue that further here.
[9] However
note that Popper later repudiated this analysis, as I 
discuss in section 5.2.
[10] There may be a lingering misconception that all
  tautologies are equivalent, so that the
  possibility of "distinct" tautologies cannot arise; this is
  not the case. All tautologies have the same truth value
  (namely, unconditionally "true"), so that they are 
  logically equivalent-but this is not at all the same
  thing. "Cats are a kind of domesticated feline" 
  and " tex2html_wrap_inline1596 
  is the ratio of the circumference to the diameter of a circle"
  are (qua definitions) two different
[11] See
(Gould 1978, Essay 4) for a more detailed
discussion of whether Darwin "really" endorsed the idea
of necessary progress in evolution.
[12] In this respect, the
  term "adaptationist" is unfortunate, as it
  invites a form of the tautology misconception 3;
  "selectionist" might be less prejudicial.
[13] tkpw/popconf/popconf.html

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TCR Issue Timestamp: Tue Dec 31 17:37:08 GMT 1996