being?

I never thought that the term "being" could mean so many different things. J.P. Satre spoke and lectured about the three different kinds of beings:

1. Being for itself

2. Being in itself

3. Being with others

The one which intrigues me the most is "being with others" and the idea of intersubjectivity and that we have to believe that others are conscious beings like ourselves... that kinda freaks me out. It seems like a reasonable assumption, right? I would think so.