The end of education is wisdom. Man desires by nature to know, and that means we want to have not only the facts, but the reasons for the facts. We want to think about the highest things, the most noble, the most interesting in themselves.
There are steps in such an education. One can't begin by studying the very highest things.... Why not? Because the student won't be able to understand what he reads. He needs to do some preliminary work. But that preliminary work is ordered to eventually understanding the very highest truths.
Liberal education, which we also call classical education, is such an education. It begins in wonder and aims at wisdom.
The part about "all men by nature desire to know" comes from Aristotle, and the reference to wonder and wisdom is from Plato.
Liam said today that people naturally tend to ask "Why?" and keep asking until they get back to the First Principles, or final answer. I was thinking that maybe that idea would help me unify all those scattered homeschool subjects. But we'll see.