Liu Cixin's trilogy Remembrance of Earth's Past gives an interesting aspect to that question, comparing galactic civilizations with hunters in a dark forest:

In a dark forest, you have no way to identify if anyone you meet is peaceful or not. So the only rational way (if you want to survive) is to hide yourself - and to kill any other before they might see and kill you.

So I'm not so sure if I want to find out if there is extraterrestrial life ...

Rata