I thought "Let That Be Your Last Battlefield" ended with Spock saying something like, "But it is in our difference that we find meaning." I can't find such a quote. Help!

Here's a link with all the 名言・格言 from that episode, but I'm not sure if the quote you're talking about comes from any 星, つ星 Trek episode from TOS, TNG, DS9, VOY または the others.

link