Question: why do we cry tears of joy?

Rebecca Dewey answered on 17 Jun 2015:

We’re not really sure – but these are two possible answers: (1) it might be that because the joy we are experiencing is so extreme, we’re just so unable to respond in a sensible way, so anything can happen: crying, laughing, anything. Or (2) in order to recover from such a huge amount of emotion that tips the balance so far to the positive, we cry to help ourselves return back to normal as quickly as possible.