Why can't a rock be alive?

life - what does that mean to you. its a vast word .every person has his own view . its quit difficult to describe it but perhaps we all undrstand it , even a small child can tell one if a rock is alive or not. But most of the time we are speaking in a language which others had taught us. we should go outside this barrier and learn a view which is sacerdly ours. Here is some which I had learnt. I am not saying that this one is the true definition of 'life'. In fact I am not defining it at all. It's just a view I beilive , a view from a different angle.

when we say that a "person is alive" , what we mean is not about his cells of the body , niether about his whole body (as an aggregate of cells & tissue ) .Then what we mean is about the person. it will be more clear if we take the example the other way, that is if we say that he is dead (just died ). Certainly , not all the cells his body is made up of has died. Still he is dead because we are talking about that particular person not about his body. life is possible at many levels. Simplest one are certainly the prokaryotes