Thursday, March 16, 2006
Peter van Inwagen on Evolution
Peter van Inwagen is a respected Professor of Philosophy at Syracuse University. Although van Inwagen is a Christian, he is not a creationist. Indeed, regarding creationism Inwagen writes: 'It's not that it's not science at all... It's that - in my view, at least - it's very bad science, consisting of contrived, ad hoc arguments and selective appeal to evidence.' Nor, from what I know, does Inwagen count himself as a supporter of Intelligent Design Theory. Nevertheless, Inwagen has doubts about the Darwinian theory of macroevolution by natural selection. Here are some excepts from Inwagen's paper on 'Genesis and Evolution', first published in 1993, which bear a strong resemblance to the writings of several ID theorists:
‘One of the strongest reasons for being sceptical about... macroevolution is the absence of intermediate forms. This absence is striking, even at the level of the biological class... there are few, if any, remotely plausible fossil candidates for intermediates between... any class and the class out of which, by general agreement, it is supposed to have evolved... I find it difficult to believe that some fish was separated from some amphibian by only – to pick a figure that must be right within a factor of two or three – ten thousand generations, each of which differed from its predecessor only to the extent allowed by the operation of natural selection. Most biologists, apparently, find this easy enough to believe. The ignorant skeptic like myself, the village atheist, will wonder whether their ability to believe this is rooted in their nuts-and-bolts anatomical, physiological, and biochemical expertise, or whether it is the product of their belief that things could easily have happened this way because this is how things did in fact happen... One can also raise the question whether the missing intermediates are even logically possible, given that evolution proceeds by natural selection... there is no guarantee that such a procedure would produce at each step a genotype that corresponds to a viable organism. In fact, I find it hard to believe that it would... I doubt that there is any path in logical space from one to the other that proceeds by changing a small number of genes at each step: every path you try will (I suspect) eventually run up against organs and systems that are no longer coordinated – perhaps even against proteins that don’t fold properly. You can only look from one to the other and shake your head sadly and say, “You can’t get there from here.” At least not by the mode of transport envisaged... even if there are possible “small-step” paths from fish to amphibian, these paths might compose only an infinitesimally small region within the space of all the possible paths that confront the ancestral population of fish, and thus the evolution by natural selection of amphibian from fish might be so vastly improbable as not to be worth considering… our tentative conclusion should be that the theory of evolution by natural selection alone is doubtful in a way that many scientific theories are not.’ - Peter van Inwagen, ‘Genesis and Evolution’ in God, Knowledge & Mystery: Essays in Philosophical Theology, (Cornell University Press, 1995), pp. 128-162.
‘One of the strongest reasons for being sceptical about... macroevolution is the absence of intermediate forms. This absence is striking, even at the level of the biological class... there are few, if any, remotely plausible fossil candidates for intermediates between... any class and the class out of which, by general agreement, it is supposed to have evolved... I find it difficult to believe that some fish was separated from some amphibian by only – to pick a figure that must be right within a factor of two or three – ten thousand generations, each of which differed from its predecessor only to the extent allowed by the operation of natural selection. Most biologists, apparently, find this easy enough to believe. The ignorant skeptic like myself, the village atheist, will wonder whether their ability to believe this is rooted in their nuts-and-bolts anatomical, physiological, and biochemical expertise, or whether it is the product of their belief that things could easily have happened this way because this is how things did in fact happen... One can also raise the question whether the missing intermediates are even logically possible, given that evolution proceeds by natural selection... there is no guarantee that such a procedure would produce at each step a genotype that corresponds to a viable organism. In fact, I find it hard to believe that it would... I doubt that there is any path in logical space from one to the other that proceeds by changing a small number of genes at each step: every path you try will (I suspect) eventually run up against organs and systems that are no longer coordinated – perhaps even against proteins that don’t fold properly. You can only look from one to the other and shake your head sadly and say, “You can’t get there from here.” At least not by the mode of transport envisaged... even if there are possible “small-step” paths from fish to amphibian, these paths might compose only an infinitesimally small region within the space of all the possible paths that confront the ancestral population of fish, and thus the evolution by natural selection of amphibian from fish might be so vastly improbable as not to be worth considering… our tentative conclusion should be that the theory of evolution by natural selection alone is doubtful in a way that many scientific theories are not.’ - Peter van Inwagen, ‘Genesis and Evolution’ in God, Knowledge & Mystery: Essays in Philosophical Theology, (Cornell University Press, 1995), pp. 128-162.
