Comment by wsng

As part of a smalltalk training, we had to go out and approach strangers in the public. I entered a tram to try my luck. As soon as as I sat down, someone else started to talk to me, and we had a nice conversation. I didn't even need to break the ice myself. So I can (anecdotally) confirm that people can perceive if you want to connect or rather want to be left alone.