Clarifying Plantinga's Epistemology
I won’t defend Plantinga’s epistemology but I will explain it for user John Appleseed, who wonders…
I think Mr. Appleseed will be relieved to hear his interpretation is not (exactly) correct. Plantinga is an externalist with respect to knowledge, who focuses on warrant, which, according to Plantinga, is that quality that can bring us from true belief to actual knowledge. In Plantinga’s words: “Warrant is the property enough of which is what distinguishes knowledge from mere true belief.” (Knowledge and Christian Belief, pg. 25.)
As Plantinga explains, it’s obvious you can have true belief without knowledge, “You have travelled 2,000 miles to the North Cascades for a climbing trip; you are desperately eager to climb. Being an incurable optimist, you believe it will be bright, sunny, and warm tomorrow, despite the forecast, which calls for high winds and a nasty mixture of rain, sleet, and snow. As it turns out, the forecasters were wrong and tomorrow turns out sunny and beautiful: your belief was true, but it didn’t constitute knowledge. What is needed, in addition to truth, for a belief to be knowledge? I’ll use the term ‘warrant’ to name that property, whatever that is.” (Ibid.)
Plantinga famously argues a belief has warrant IFF that belief is produced by cognitive faculties that are functioning properly in a conducive environment and that those cognitive faculties are aimed at true belief and generally good (have a high enough probability) at getting it.
The relation to theism is this. If God exists, then probably God designed us to know truth and probably his design plan is a good one. In which case, belief in God, which is occasioned in us in a way similar to our belief in the external world or the existence of other minds, can be classified as “properly basic”: that is, a belief that is rational to hold APART from argument and is, in fact, warranted absent defeaters.
If God does not exist, then Plantinga’s (in)famous evolutionary argument against naturalism kicks in, which seeks to create an epistemological nightmare for atheists — namely, that naturalism PLUS evolution results in a position where even if naturalism PLUS evolution were true, we could never have knowledge that it were true. It’s a technical argument and patient reading of it is required. My recommendation? Start with Warrant and Proper Function. Then go to Where the Conflict Really Lies.
Anyway, much of what Plantinga does throughout his books on epistemology is not just to argue for his account of proper functionalism but to argue for God as a properly basic belief that has no undefeated (or undefeatable) defeaters. In short, Plantinga is attempting to show that belief in God is as reasonable and warranted as belief in the external world, or the existence of other minds, etc. In other words, it (belief in God) isn’t a belief that need be supported by argument or inference: Just so long as somebody doesn’t produce a reason why God doesn’t exist (= a defeater) then you are rational to believe.
However, this is different than saying our knowledge of God rests entirely on subjective experience. Because we might still HAVE independent reasons for belief in God (a cosmological argument, say); Plantinga is simply arguing that such reasons are not required for belief in God to be reasonable and responsible.
I wouldn’t dwell too much on what your subjective experience is: If Plantinga is right, simply you finding yourself believing in God — however that belief is occasioned (maybe you looked at the stars one evening and just found yourself believing, or your parents taught you, etc) — is enough.
As Plantinga explains, “… this natural knowledge of God is not arrived at by inference or argument (for example the famous theistic proofs of natural theology) but in a much more immediate way. The deliverances of the sensus divinitatus (sense of the divine) are not quick inferences from the circumstances that trigger its operation. It isn’t that one beholds the night sky, notes that it is grand, and concludes that there must be such a person as God: as an argument, this would be pretty weak. … It is rather that upon the perception of the night sky or the mountain vista or the tiny flower these beliefs just arise within us. They arise in these circumstances; they are not conclusions from them. The heavens declare the glory of God and the skies proclaims the work of his hands (Psalm 19): but not by way of serving as premises for an argument.” (Pg. 35.)