This is a rather broad topic, isn't it? Seems a lot for one thread, but I digress.
Philosophy on "life", eh? Well, to me, from my own experiences, which is really all that anyone can base their opinions off of, life is a state of existence that is characterized by concious thought. The old Descartes quote, I think, therefore I am, applies. I don't know that anyone else around me thinks and therefore, I cannot validate their existence. Some may notice that animals and plants would not be considered alive by my definition, but keep in mind that my definition is only what I know for certain. I don't know that animals and plants are truly alive; all I know is that they are alive by the material world's standards, a world that may not even exist. Of course, I'm not arrogant enough to claim that I am the only thing that exists. The material world may very well exist, I have no way to prove it does or does not as yet, but what I do know is that I am the only being that I can prove to myself exists and is alive (even that is not a definite actually, as artificial intelligence could create various shades of grey on that topic).
I think that's what the topic of this thread was. It's kind of vague.
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