Clark recently mentioned Eco's The Search for a Perfect Language. Here's a quote from that book that I wrote down in my notes when I read it last year or so:
It is frequently claimed in American philosophy departments that, in order to be a philosopher, it is not necessary to revisit the history of philosophy. It is like the claim that one can become a painter without having seen a single work of Raphael, or a writer without having read the classics. Such things are theoretically possible; but the 'primitive' artist, condemned to an ignorance of the past, is always recognizable as such and rightly labelled as a naïf. It is only when we reconsider past projects revealed as utopian or as failures that we are apprised of the dangers and possibilities for failure for our allegedly new projects. The study of the deeds of our ancestors is thus more than an antiquarian pasttime, it is an immunological precaution.