As I will describe, an “Evidentialist” is anyone who subscribes to what we will call the “Evidentialist Credo”. Though many theists have been committed to this credo, it is easiest to explain by looking at an argument offered by many atheists. Evidentialism
Evidentialist Objection
The “Evidentialist Objection” is a very straightforward argument against theistic belief. It runs as follows:1. One ought not to believe something upon insufficient evidence.In response to this Objection, Plantinga makes a number of claims. In one sense he clearly thinks that the second premise is much too strong; he points out that there is a long distinguished history (Natural Theology) of discovering the evidence for the existence of God. (In articles other than the one we read, Plantinga himself attempts to uncover evidence for God's existence.) However, as we have seen, he wishes to spurn Natural Theology.
2. We have no sufficient evidence for the proposition that God exists
C. One ought not believe that God exists.So, in the end, Plantinga is willing to concede the second premise; his real interest lies with the first premise.
Evidentialist Credo
I referred to the first premise of this Evidentialist Objection as the “Evidentialist Credo”:"One ought not believe something upon insufficient evidence."(Notice that this seems to be the key claim in Flew's case for his Presumption of Atheism.)The most important point of the Evidentialist Credo is that the “ought” of the credo expresses a duty. (As I described in the supplemental notes page, Clifford interpreted the duty as a moral duty, but there is a less controversial sense in which you have a duty to proportion your beliefs to the evidence that you have.) We don’t let a person “get away” with having absolutely no reasons for believing what she does. Of course we don’t punish them as we would if they flouted a moral duty, but we do ascribe a certain failure to them: the failure of rationality. Simply put, we think such people are irrational, and all things considered it’s better not to be one of those people.
Natural Theology
Obviously, anyone who offers the Evidentialist Objection is committed to the Evidentialist Credo. However, it is important to note that many theists have also been committed to this claim. As Plantinga describes, Aquinas and the other members of the Natural Theology tradition all hold the Evidentialist Credo.Plantinga and Kretzmann
As we saw, the dispute over the Evidentialist Credo is central to the dispute between Plantinga and Kretzmann.Back to PlantingaPlantinga attempts to object to the Credo. Kretzmann then attempts to respond to Plantinga on the Evidentialists’ behalf.