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 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 ( ), 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. 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 latter.  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).  I find the latter term to be seriously confusing. This is discussed at length in (McMullin 1992c).  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 stand.  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!  This thesis is commonly expressed by saying that variation is "random"; but that term is very vague and ambiguous.  Admittedly, it is a moot point whether this is true of unicellular organisms; but I shall not pursue that further here.  However note that Popper later repudiated this analysis, as I discuss in section 5.2.  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 " is the ratio of the circumference to the diameter of a circle" are (qua definitions) two different tautologies.  See (Gould 1978, Essay 4) for a more detailed discussion of whether Darwin "really" endorsed the idea of necessary progress in evolution.  In this respect, the term "adaptationist" is unfortunate, as it invites a form of the tautology misconception 3; "selectionist" might be less prejudicial.  http://www.eeng.dcu.ie/ tkpw/popconf/popconf.html  http://beast.cc.emory.edu/Jargon30/JARGON_C/CONSHARM.HTML
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TCR Issue Timestamp: Tue Dec 31 17:37:08 GMT 1996