To be erudite is to display knowledge, but in a good way. No one likes a show-off because show-offs are rude, but to be erudite is to share knowledge because knowledge itself is a precious thing.
To be erudite is the opposite of rude: which, for someone interested in the origins of words, is immensely satisfying.
Thing To Be Today: erudite. Erudite means, at root, not rude. The e at the beginning is short for ex- which means outside of, and the rud bit comes from the Latin word rudis, which means unpolished or rough.
To be myself erudite for a moment, the rude mechanicals in A Midsummer Night's Dream, are rude in the same way (as, actually, are all rude people).