if there are 4 dismonds on the board?

You should just fold and not chase cards. That's how you end up losing chips fast. Especially online.

Definitely need more info on the play. Just because he has a diamond doesn't mean it isn't the 3 of diamonds and he is just as worried about you running into the flush with a J of diamonds in your hand

Actually, the way the hand was played does not matter what so ever, he asked for the Odds of the other player having a diamonds in his hands, odds are numbers, period. Not "feelings" nor "reads"

if there are 4 diamonds on board and you don't have any.... GET OUT LOL