According to astrophysicians:
A localized and temporary system which defies laws of physics: negative entropy
Everything that exists deteriorates with time, except life (as long as it lives).

Maybe searching for other signs of negative entropy would be interesting..But no one knows what it would look like.

According to an astrochemist: the production of a lot of oxygen (no other known process produces that much oxygen)

According to an anthropologist:
Most traditional cultures don't separate the living from the inanimate like western culture does. This made it possible to master nature (as we're separate from it) and also is the source of the pollution we produce. This is perhaps also why we want so badly to find extra-terrestrial life!

According to a philosopher:
Life is a process producing meaning. A machine has no goal. If it were no more controlled, it would go on doing what it does without intrinsic finality. However, it's not because there's a direction, a finality to life, that it has a goal. Life is searching and inventing goals all the time. According to Bergson, the living beings intrinsic finality is the creative force ...

According to a religious:
Life is a divine, mysterious and sacred spark....

Well, lots of different interpretations...and lots of conflicts because of different interpretations (when religion gets involved, for instance)....

But what is a creative force, a sacred spark? Isn't that also a source of conflict?

Real scientists must be closer to the real interpretation than philosophers and religious.