How reliable do you think your cognitive facilities are? Your eyes, ears, etc? Your brain, memory and mental processes? According to philosopher of religion Alvin Plantinga, not very good. He asserts any belief you form using these facilities is as likely to be untrue as it is to be true. “A probability of 0.5″ he says – like a magician pulling a rabbit out of hat.
But it gets worse. For some reason he thinks your beliefs are formed randomly – so “If I have one thousand independent beliefs, for example, the probability (under these conditions) that three quarters or more of these beliefs are true will be less than 10–58.” When he considers only 100 independent beliefs “the probability that three-quarters of them are true, given that the probability of any one’s being true is one half, is very low, something like .000001.”
So, you wonder – how the hell do you get by? You are in the middle of the road, a bus is speeding towards you, but the chance of your cognitive facilities leading you to believe you are in danger is minuscule. You are just as likely to belief you are having a pleasant bath – or a gazillion other things.
That doesn’t sound right, does it? Something is fishy here. Surely natural selection will have weeded out organisms which had such poor cognitive facilities millions of years ago. Well, according to Plantinga, no! Unless evolution was guided by his god! He just thinks that unguided evolution is incapable of producing reliable cognitive facilities. In fact, he claims evolutionary science supports him saying: “The scientific theory of evolution just as such is entirely compatible with the thought that God has guided and orchestrated the course of evolution, planned and directed it, in such a way as to achieve the ends he intends.”
He argues that unguided evolution is “prohibitively improbable.” Not surprising to see that he has a soft spot for Michael Behe‘s irreducible complexity argument against evolutionary science (and for “intelligent design”). Plantinga’s recent book ( Where the Conflict Really Lies: Science, Religion, and Naturalism) is full of theological pretzel twisting, motivated logic, unsupported logical possibilities, probability assumptions, cherry-picked quotations, and bald statements supporting his claims. But, unhappily for many of this theological supporters, he is also very careful to include qualifications for almost all his claims and arguments. This gives him deniability, wriggle room, but makes it difficult for his supporters to find supporting evidence for his claims.
Here I will deal with just his claim that evolution via inherited variation and natural section is incapable of producing reliable cognitive facilities. Even here he claims he is not arguing: “that unguided evolution could not produce creatures with reliable belief-producing faculties; I very much doubt that it could, but that it couldn’t is neither a premise nor the conclusion of my argument.”
Still, that is exactly what he does argue. He says “it is improbable, given naturalism and evolution, that our cognitive faculties are reliable.” That his god “could have brought it about that our cognitive faculties evolve by natural selection, and evolve in such a way that it is natural for us to form beliefs about the supernatural in general and God himself in particular.” “that God has created us in such a way that we come to know him; and the function of the cognitive processes, whatever they are, that ordinarily produce belief in God in us is to provide us with true belief.” And “According to John Calvin, God has created us with a “sensus divinitatis,” a natural tendency to form belief in God.”
So you can see where he is going with this. Belief in a god seems to be an indicator that your cognitive system is working well, whereas non-belief shows its not! You atheists have something missing from your brain.
Naive survival argument
Plantinga’s argument centres on a naive interpretation of natural selection:
“We might think that our evolutionary origin guarantees or strongly supports the thought that our basic cognitive faculties are reliable: if they weren’t, how could we have survived and reproduced? But this is clearly an error, . . . . . Natural selection is interested in adaptive behavior, behavior that conduces to survival and reproduction; it has no interest in our having true beliefs.”
And his followers see that as a key premise in his argument.
However, if a particular inheritable variation is selected because it aids survival or increases number of offspring this does not prevent that particular variation contributing to the life of the organism in other ways. A cat’s paw enables it to move, to pursue prey and avoid predators but this in no way prevent cats from using their paws in grooming.
We can understand how selected variations in our ancestors perception organs, brains, and the rest of their body, would have had survival and reproduction values. Tool-making abilities, a thickened pre-frontal cortex, language abilities, self-reflection and recall of memories would have contributed greatly to the natural selection of our ancestors.
But once selected, not only did our ancestors become more social, more able to communicate and more able to change their environment with the tools they created. They also were able to use their perception and cognitive faculties in a more advanced way. To formulate more detailed pictures of their environment and to check out the accuracy of those ideas or beliefs. And to pass on this knowledge to their offspring.
It is just overwhelmingly naive not to recognise the wider implications of variations selected by the evolutionary process beyond survival and reproduction. And it is dishonest to cherry-pick, as Plantinga does, quotes from evolutionary scientists and philosophers which stress the role of survival and reproduction in natural selection as if there were no other consequences for the evolution of the selected organisms.
Why is it so hard to see the natural selection of intelligence in our ancestors has lead to huge technological and cultural changes quite above and beyond its value for survival and reproduction? Why should Plantinga accept that unguided evolution can lead to intelligence for its value in survival and reproduction but drag in the concept of guided evolution by his god to explain the resulting cultural, technological and social changes?
Reliability of cognitive facilities – something more than chance.
I find weird Plantinga’s idea that guidance of evolution by his god is necessary for our cognitive faculties to produce reliable results. Even weirder that in the absence of such guidance natural selection would produce cognitive faculties which caused us to adopt beliefs completely randomly. Surely such faulty cognitive faculties would have been selected against? And those organisms whose cognitive faculties produced a sufficiently reliable picture of reality (or belief) to enable survival and reproduction would have been selected for.
Plantinga confuses his argument by steadfastly referring to “belief” and “true belief” whereas the day-to-day life of an organism requires (usually unconscious) perception or knowledge of its environment and reaction to what it perceives. In effect, the organism, and particularly a species like humans, is continually forming a mental image or model of its environment. The accuracy of this model relies on the abilities of the perception organs, the unconscious aggregation of perceptions and memories to form a mental image and the amount of conscious deliberation. We can be sure that this knowledge never amounts to a completely accurate model of reality. All sorts of practical assumptions are made for the sake of efficiency. And animals like us are just not able to perceive bacteria and molecules, let alone atoms or subatomic particles.
So our mental model of reality will always be imperfect. It can never be identified with Plantinga’s “true belief.” But it is good enough for what we are doing – surviving, reproducing, making tools, telling stories, formulating theories, etc. And we quite naturally pay special attention when we need to fill out details. Or we can resort to tools and instruments which aid our perceptions.
If natural selection working on genetic variation has produced animals capable of surviving and reproducing by using their perception organs, intelligence, memory and imagination why should it be impossible (as Plantinga claims) for such animals to form “belief”, or knowledge about reality, which, for all practical purposes, can be considered “true?” Why does he claim guidance by his god is necessary?
When I hear this term “theistic evolution” used I never know what is intended. At one end it could just be that a person who claims to believe in theistic evolution is only saying they accept evolutionary science, while at the same time they are a Christian. Perhaps its just a way of avoiding criticism from their fellow church members. An assurance that their acceptance of evolutionary science does not signal rejection of their faith.
The adjective “theistic” is actually unnecessary – except for social purposes. One could equally say they believed in “theistic gravity,” “theistic chemical reactions,” etc. Sounds silly – but I guess social pressure produces silly conventions and scientifically meaningless terms.
At the other end of the spectrum I think the person is actually claiming a belief similar to Plantinga’s. That evolution is actually impossible without divine interference, specifically guidance from their god. They may imagine that their god actually fiddles with the atoms in an organism’s DNA, or aids selection with a flood, collision of an asteroid or a volcanic eruption or two. Even, as some of these people claim, the divine injection of determinism into quantum indeterminacy
Of course, people who claim such guidance is required for evolution to work just don’t accept the current scientific understanding of the evolutionary process which is very much unguided (except through the natural selection process). If adherents of “theistic evolution” mean this, something like Plantinga’s “evolution” then they don’t accept evolutionary science.
And that’s why I just don’t like the term “theistic evolution” and am always suspicious of people who describe themselves that way.