I did a seminar recently called 愛と恋 (teenager relationship advice thingy) and asked the guys to tell me what they saw as the difference between them. (I had to translate the title into English and couldn't get past "Love and love".)

The winning answer was "恋は下心、愛は中心".

中, that sounds about right. Did anything reach 上 in their estimation?

That's the best aphorism ever. :)

Ah, now you're getting it, with the 下中上 scheme. I am reminded of one of my favorite eccentric Japanese culture books, "Haragei." The author argues there are three centers of Japanese feelings, hara, kokoro, and atama. Gut feelings are most fundamental, the heart is central (figuratively as well as literally) but the head is full of thinking and thus not to be trusted. Of course it's a ridiculous nihonjinron but I laughed and laughed at the book, it's worth a read (if you can find it, it's out of print).

Ooh dabbling in the dark arts of conceptual analysis, are we. You bring the pentagrams and I'll get the goat entrails.

Nihonjinron frameworks aside, asking about the difference between 愛　and 恋　made me wonder if anyone can recommend a good collocation dictionary (or other modern corpus-based dictionary) for Japanese? There are a few out there apparently, but I'd love to hear some reviews if anyone's used them.

I'm looking for a good dictionary along those lines too, JPS, but I haven't found one yet. I'll be sure to post about it if I do!