What is life ... continued ...

Someone made a comment on my earlier post, here's something that'll make him think.

Do we only exist at the physical level? If this is all there is to our existence, why do we think about it? What is it that makes us sentient? What is it that seems to live two or three inches behind our eyes and that looks out into the world? Why do we exist?
Without getting too philosophical [Sidd :)], we can reasonably assume that chemistry, maths or physics dont define our existence completely. Can chemical compounds love each other? Can they feel sad? Happy? Can they grieve when other chemical reactions have run their course? Can they wonder where they came from and where they will go? Can they "live"?

Eh, Pascal??