Human mind is so inquisitive that it wants to understand everything. From how the Universe Started to How It will end and What happens to you after you die and what actually constitutes a soul. Similarly, what is life? also stimulates a lot of thoughts but I think it does not have a definition and it is best to leave it that way. If life was explained, it would not be mysterious anymore and I think it would lose its charm. So I would say Life is Life