From Aristotle to Darwin and back again: a journey in final causality.
Quoting OoS: "..... In the first place, varieties, even strongly-marked ones, though having somewhat of the character of species--as is shown by the hopeless doubts in many cases how to rank them--yet certainly differ far less from each other than do good and distinct species. Nevertheless according to my view, varieties are species in the process of formation, or are, as I have called them, incipient species. How, then, does the lesser difference between varieties become augmented into the greater difference between species? That this does habitually happen, we must infer from most of the innumerable species throughout nature presenting well-marked differences; whereas varieties, the supposed prototypes and parents of future well-marked species, present slight and ill-defined differences....."
Gilson writes: "...Every attentive reader of Darwin is familiar with the expressions good species or true species, the good species implicitly contrasted with the bad, the true species with the false...."
We can see here the good/bad dichtomy from Gandalf the tribal wizard, Sumerian pagan fire/water fight religions, Empedocles and Democritus with his good bad atoms, reformulated for us differently by Darwin with his good rabbit adapted to the environment. "you are adapted to your environment" was in terms of Aristotle's "constituted internal spontaneity" for which the word "fitness" was used in 1870. The constituted atom possessed a higher spontaneous fitness than the 'bad' atom. After the fight between the good and bad atoms, the good atom was adapted to its environment.
The theory is dead, logically. Though it may be salvageable under a different understanding.
It has to do with it's philosophical problems. Not only is the mechanism changed regularly (as in gradualism to punctuated equilibrium ) but the 'survival of the fittest' is a tautology, as in whatever survives is called the fittest.
I only answer this post to alert interested parties to the re-release of a 35 year old book that was crucial to my rejection of Evolution.
From Aristotle to Darwin by Etienne Gilson Due out in a month.
" A more accurate title for Darwin’s book, according to Gilson, would be the Origin of Varieties. Darwin’s use of the word “species,” however, is contradictory. “To say that species are fixed,” Gilson writes, “is tautology; to say that they change is to say that they do not exist, Why does Darwin obstinately say that they transform themselves, rather than saying simply that they do not exist?” (pp. 140-144)"