Perhaps an analogy will help. He may have adopted an empirical epistemology which leads him to that conclusion. He is, in effect, a good scientist, but a bad philosopher. The same is true in the social sciences. But his bad philosophy does not invalidate the truthfulness of his first statement.
Men do learn some things by conditioning.
Perhaps not solely by conditioning, but it is an important element in some learning. The social science method of observation, classification, and prediction of probability is a valid tool and can be used by those who hold distinctly Wesleyan presuppositions. Let me illustrate with an example which precedes even modern social science methodology. In the 1820's, a young preacher by the name of Charles Grandison Finney began evangelistic tours in which he developed methods for effective evangelism. A miracle has been generally defined to be Divine interference, setting aside, or suspending, the laws of nature.