And now for something completely different - what makes us human?

The argument has been that language makes us uniquely human.  Here is a brief review of a provocative book that argues that it is our recursive mind that does so.  In other words, our ability to embed thoughts in other thoughts.  I don't know what I think about it but I think there is a pony underneath this somewhere.

Recursion enables us to conceive of our own minds and the minds of others. It also gives us the power of mental “time travel” — the ability to insert past experiences, or imagined future ones, into present consciousness.

It kind of sounds like the concept of a soul - a unique, self aware entity that can process normative concepts of good and evil and of past and future.  In other words, an entity with rather God-like capabilities.  Perhaps even something made in the image of God.

Once again biology, philosophy and theology bump up against each other.  Roughly.