It becomes increasingly apparent that the teacher in Dewey’s schools must somehow know that these teachings of Christianity cannot be true. They must protect their pupils from the evil influences of such disintegrating and miseducative doctrines. So they must be sure that these doctrines are not true. They must know that it is impossible that they can be true. They must be able to assure the pupils that there cannot be a judgment coming. They must be able to make universal negative assertions about all future experience. And they must make such assertions on the basis of present experience as it is intelligible without reference to anything beyond itself. In other words Dewey’s teachers must first assert that man knows nothing of a transcendent realm. But they must also assert, in effect, that they know all about it. They must assert that nobody knows anything about it. This means that they who claim to know about it must be mistaken. And then they themselves, nonetheless, presume to know all about it. They must be omniscient in order to know that no one can rightfully claim to know anything about God.
– Cornelius Van Til, The Dilemma of Education p.5