One of the most popular and long lasting philosophical questions is ‘what is life?’ It is an empirical question, one that may be answerable only by science, though not without an argument, and not without giving different answers to the same question in different circumstances. Life is a living entity that distinguishable by biological processes, like self-sustenance and signaling processes, from non-biotic ones, like chemical self replicating systems, and because these processes have stopped, or because they have never had these biological functions, are classed as non-biotic. The most important characteristics of life include breathing air, using energy to move about, getting oxygen, consuming food, reproducing itself, and interacting with its environment. To give a more detailed definition, here is one well-known definition of life given by the philosopher Kurt Goldstein: “Life is the ability to function for the benefit of living”.
Another long-time question, which is very often asked, is “what is the meaning of life?” Many psychologists and ethologists think that there is no meaning; rather, it is the product of a human interpretation of the world. For example, if you ask an alien who is looking at your garden whether he found it beautiful, he will reply, withoutuding to any deeper meaning, that it is beautiful because it gives him pleasure, since he is alive, and that to him, a garden is a place where one can find pleasure and be happy. From this, many people conclude that the meaning of life is pleasure. But another school of thought maintains that it is the meaning of life because to a naturalist, what is beautiful to one person, is not necessarily so for another. It is an essential problem for philosophers to decide what is the meaning of life, since it is in their scientific enterprise to discover the criteria by which we may say that everything exists.
A more pressing question is “why does man feel insecurities about life and the world around him?” This too is a very difficult one to answer, because to a man, the reason for feeling insecurities is usually very personal and has to do with his role in society, his education, his ability, his success, his relationships and with other men or women. One must therefore take into account the social aspects of one’s life before one can answer what is the meaning of life. The modern man is often a creature of his times, and as such, tends to look back on his past with a sense of nostalgia and an awareness that things were much simpler when life was simpler.