Here's a taste:
The ancient Romans had slaves from all over the world. Some of their slaves, like the Greeks, were bright, and the Romans controlled them by limiting their education. Romans allowed slaves to be educated in math and engineering so they could build things, and in the arts so they could entertain, but only Roman citizens (free people) could study history, rhetoric, or philosophy - the exclusive privilege of the liberi, the free men.
True thinking is work. It involves being comfortable with not knowing, and that flies in the face of punditry. But if we want to truly understand what we read on the front page, or be able to sort through both NPR and Rush Limbaugh, we have to practice on tough material - such as literature or philosophy - which might temporarily confuse, but will ultimately free us all.