Alvin Plantinga

Alvin Plantinga is a professor of philosophy at Calvin College in Grand Rapids, Michigan. He spent nineteen years as a professor at Calvin College, then eighteen years at the University of Notre Dame, and returned to Calvin College in 2010. He is most known for his Christian apologetics and defenses of dualism and free will. Like much apologetics, his work in this area repackages many age-old arguments. In Plantinga's case, he has reformulated many arguments from the Reformed (Calvinist) tradition such as sensus divinitatis. He also has no understanding whatsoever of evolution and considers his lack of understanding constitutes making important points.

Warrant
Plantinga's significance in contemporary analytic philosophy stems from his work on modal logic and his work in epistemology contained in three books: Warrant: The Current Debate, Warrant and Proper Function and Warranted Christian Belief. In these three works, Plantinga builds up a theory that attempts to provide a framework for answering the question: for the beliefs we have, to what degree are we warranted?

The first book, Warrant: The Current Debate (1993), explains the basic premise of this inquiry and why the terminology of warrant is preferred over other epistemological terms (broadly, because Plantinga believes that a lot of other terms used to signify this state of positive epistemic status presume the conclusions they seek: for instance, saying warranted beliefs are justified presumes that an account of beliefs being based on justification is the correct epistemological theory).

Plantinga presents a variety of answers from the epistemological literature but finds fault with them because of their failure to deal with the challenge of "cognitive malfunction". Needless to say, the counter-examples he presents are hypothetical and speculative rather than medically accurate. In Plantinga's view, a theory must be able to resist all possible logical counter-examples (even if the scenarios described in those counter-examples are physically impossible in the actual universe we live in, or indeed highly improbable).

As the philosopher Tyler Wunder notes, near the end of Warrant: The Current Debate, Plantinga shifts his standard of evidence before he presents his own theory:

Plantinga insulates his theory from the challenge of having to satisfy all possible logical counter-examples by setting a new standard... but doesn't apply that standard to the theories he's already rejected. Sneaky.

Warrant and Proper Function (1993) presents Plantinga's theory of warrant, which he describes as a theory of "proper function". The theory is used in the book to jumpstart an argument against naturalism: namely, that if one is attracted to Plantinga's theory, it is—Plantinga says—very hard to square with a naturalistic understanding of evolution if you don't presume that there is a God.

Warranted Christian Belief (2000) applies Plantinga's account of warrant to religious—specifically Christian—beliefs. Plantinga comes to the somewhat startling conclusion that religious believers have a built-in module for believing in God, a sensus divinitatis. Belief in God is thus justified as a "properly basic" belief in the same way that perceptual beliefs about the world around us are—because believers get a direct knowledge of God through the sensus divinitatis, much as we get direct experience of the visual world through our eyes. Pesky atheist types don't get any such experience because of the "noetic effects of sin". Which is very convenient.

Some arguments for and about God
Plantinga self-defines as a Christian apologist, but many of his writings define his God as far more theistic or deistic in nature.

Ontological argument
Plantinga defended a modal ontological argument, which essentially rests on defining God in such a way that they "must" exist.

God as basic belief and necessary being
Plantinga argues that God can be accepted without proof just as the existence of other minds can - what is called a "basic belief", that is axiomatic. A skeptic of the analogy to the existence of other minds would argue that this isn't actually taken on faith. That another mind exists inside another human being is a strong inference based on outward observations, as humans pass the Turing test (or at least should pass). The fields of psychology, cognitive science, and neuroscience make it possible to extend basic observations to looking at the structure of the brain and the isomorphism between that physical structure and the human mind - all evidence that makes it highly unlikely that other minds don't exist. The existence of God, specifically any Judeo-Christian one that Plantinga supports, isn't based on this sort of evidence.

In response to Richard Dawkins' "God hypothesis" assertion that God must be complex, he suggests that God, being spiritual in nature, is in fact simple - simple enough to be axiomatic. Russell Blackford, among others, disputes that the Abrahamic God is inherently simple; if the universe is designed, the designer must be incredibly complex, much as the human brains that design watches and telescopes are complex. We do not experience spirits as postulated by believers and theologians. According to Blackford, if we viewed the design concept unprejudiced by prior exposure to religious ideas, we would conclude that the existence of the Abrahamic God is highly improbable. Wilson Pruitt suggested that "(...)  Plantinga is not interested in proving the existence of the Christian God but warranting theistic belief. This is not a distinction without a difference."

Plantinga also supports the notion of God being a "necessary being" in addition to part of a basic belief. In this assertion, "necessary" is defined as "existing in all possible worlds". I.e., no matter what other things we change about hypothetical (or conceptual) alternative realities or futures - these aren't quite the same as the many worlds in quantum mechanics interpretations, but are constructs for the purposes of thought experiments - God must exist in each. The trouble with this is that we can conceive that in one possible world Alvin Plantinga was actually a Muslim, and formulated, through identical reasoning, that Allah is a necessary being that exists in all possible worlds. Which is the main problem with combining quite hardcore philosophy with apologetics. Not to mention that anyone could, in fact, imagine a world in which nothing exists including God, so that world would serve as a counter-example to the notion that God exists in all possible worlds. Though the notion of "possible worlds" is problematic, as we should not judge the possibility of a particular world based on how this world works, as any other world would conceivably function differently from this one (including a Godless world). The only way to make God a necessary being according to Plantinga's definition would be to exclude any world in which God doesn't exist from the set of possible worlds. The claim that God is a necessary being then is just an unjustified assertion.

Free will and the problem of evil
Plantinga recycles the free-will theodicy in an attempt to refute the problem of evil. This still fails to answer the question of evil brought about by non-human causes, such as natural disasters. He justifies this by suggesting that natural disasters could be caused by the free-will of spirits, angels, or devils, which serves to demonstrate how he is really just grasping at straws to justify his beliefs and even then still raises the question why an all-good, all-powerful God would let them wreak havoc. Is the free will of demons really so important? Also, isn't free will violated in humans killed or injured during natural disasters?

Evolution and intelligent design
Plantinga has at various points voiced support for intelligent design but claims to doubt its scientific validity. He seems to be unaware of the fact that he's arguing in favor of a form of theistic evolution rather than intelligent design. He also argues that a belief in evolution and theism are not mutually exclusive. He's right for once. However, he seems to have backpedaled on this more recently, as he devoted space in his book Where the Conflict Really Lies to defending Michael Behe's ideas about irreducible complexity.

Evolutionary argument against naturalism (EAAN)
Plantinga has argued that believing in both (atheistic) naturalism and evolution is self-defeating. He has called this the "evolutionary argument against naturalism" (EAAN). The EAAN, then, is a sort of inversion of arguments made by atheists such as Richard Dawkins that evolution is incompatible with theism. On the contrary, Plantinga argues, evolution is incompatible with atheistic naturalism. The meat of the argument may be summarized as follows:
 * Assuming naturalism, there is no source for belief-forming mechanisms other than evolution.
 * Evolution selects for belief-forming mechanisms that produce beliefs which are useful for survival (i.e., increase fitness), not ones which are true.
 * Given the conjunction of evolution and naturalism, there is no reason to think our belief-forming mechanisms are reliable.
 * The belief-forming mechanisms that led us to accept evolution and naturalism are unreliable.
 * Therefore, believing in both evolution and naturalism is self-defeating.

There are a number of serious problems with this argument. For one, there is no reason to assume that there is little to no overlap between beliefs that are true and ones that are useful. For example, if you are standing in front of a berry bush full of edible berries, it would make sense that believing that the bush is full of berries is both useful and true.

A second problem compounds the first. Plantinga quotes Charles Darwin out of context. This may seem to be a trivial detail, but it highlights the fact that Plantinga fails to distinguish between different kinds of beliefs. Darwin, in the quoted passage, did not in fact claim that evolutionary theory raises doubts about all forms of knowledge. He claimed that it made him skeptical about the acquisition of knowledge in certain domains such as metaphysics. Many other thinkers have followed in this vein by claiming that we are adapted to our immediate surroundings, so our beliefs about these surroundings will be more reliable than our beliefs about things on macro and micro scales. Our beliefs about that berry bush will be more reliable and understandable than, say, our intuitive notions about quantum mechanics and general relativity, which are counterintuitive because of the scale they deal with. It may also be the case that, as Branden Fitelson and Elliott Sober argue, only a non-negligible portion of our beliefs need to be true in order for Plantinga's argument to fall apart.

Plantinga also fails to take into consideration how scientists and philosophers have already been taking into account the implications of evolved cognitive biases on rational thought. A community of scholars will put checks on biases that may befall any individual person. While biases may not be able to be overcome, they may be tempered enough to achieve success even in counterintuitive fields such as the aforementioned quantum theory. Models of scientific processes that account for the evolved cognitive biases that Plantinga mentions have been proposed -- some even before Plantinga first published his argument!

David Hume in arguing against the analogy of design of the world suggests the competing analogy of growth. "Reason, in innumerable instances, is observed to arise from the principle of generation, and is never to arise from any other principle." That is, we observe that the appearance of reason is always associated with the natural processes of human reproduction and growth, and we have no other example.

Finally, it is not only a matter of the fallacy of the false dilemma: that even if there is a fault in natural evolution it does not prove anything positive about non-natural non-evolution; rather the very same pattern of reasoning applies to supernatural design (or whatever the supposed alternative). If our knowledge is dependent upon supernatural intervention (the alternative scenario Plantinga wishes to assert), how can we trust that? Being supernatural is not enough to inspire trust in Puck, let alone Satan. Things which are designed carry no guarantee about their expected behavior. There is an argument against the supernatural which copies the argument against naturalism: basing our beliefs on supernatural sources produces no reason to trust them. What one ought to be arguing is that because of the power of the supernatural they are reliable. But those sources had, after all, created all that evidence for evolution and created human reasoning to which that evidence seems plausible. If they make us believe that, what other tricks are they up to? Further, given the cognitive biases humans have and many incompatible beliefs (which can't all be right), we have little reason to trust our reason has been granted by a god to be largely reliable, yet this is Plantinga's claim.

Dualism
Plantinga makes a modal argument for mind-body dualism, which is pretty much a repackaged ontological argument. The argument relies on two claims. First, there is the principle of indiscernability of identicals (abbreviated II), which states that if object X and object Y are identical, then X and Y have all the same properties (this may appear to be self-evidently true, but his argument shows that there is a subtle problem with this principle). Second, there is the controversial claim that the conceivability of some scenario implies the possibility of that scenario (abbreviated C-P). Given these claims, Plantiga's argument proceeds as follows: we can imagine (and hence conceive of) a scenario in which our minds exist independently of our bodies. By the C-P principle, this entails that it is possible for our minds to be independent of our bodies. In possible worlds semantics, we would say that there is at least one world in which my mind exists but my body does not. This means that minds and bodies have different modal properties. But the II principle tells us that if objects X and Y are identical then they share all the same properties. Since minds and bodies have different modal properties, it follows (by modus tollens) that minds are not identical to bodies.
 * 1) Science fiction authors can conceive of a great deal that is impossible.
 * 2) The god or gods and goddesses of many religions are conceivable. Does that mean all these religions past and present are conceivably true?

The most significant responses to the modal argument fall into two main categories: first, the claim that it is possible for minds to exist independently of bodies has been questioned. This line of argumentation typically proceeds by calling into question the C-P principle or the claim that the fact that I can imagine something entails that I can conceive of it (in the relevant sense). Second, the claim that the II principle applies to modal properties has been attacked; it relies on the principle of necessity of identity, which is widely but not universally accepted.

As shown above Plantinga's argument can be shown to be manifestly absurd.
 * 1) While Plantinga claims to have written the book entitled "Where the conflict really lies", it is possible to conceive that he is not the author of the book.
 * 2) However, it is not possible that Plantinga is not Plantinga.
 * 3) Therefore, Plantinga and the author of the book do not share all properties, and thus Plantinga did not write the book.