Walter J. Ong, S.J.:
One reason [Marshall McLuhan] is so hard to account for is the vast range of his knowledge and his genius for spotting correlations between the most discontinuous phenomena. As I have earlier mentioned, his instant correlations have annoyed many and upset a few. But McLuhan seldom argued over his point of view. If you didn't like one insight, he presented you with another, and always had plenty more. He himself called the products of his thinking "probes." Whatever they were, they were certainly a way of teaching, if teaching means getting people to think. His observations created excitement. If as many of them were wrong as some people like to pretend, they could hardly have had the effect they had. Thousands of people have said they don't understand what McLuhan is talking about and yet have argued over him and his message for years. The discussion continues even as I write. He is still teaching, and always will be."