| Sentience is described as the state of self-awareness. Humans do not commonly see things such as ants or bees as self aware, and the moral implications that would arise if food animals were seen as sentient is far to great for society to accept, so we exist in our society contained in a bubble of ignorance, believing only us to be sentient, and perhaps the other higher apes such as chimpanzees.
Does this then mean that all other living creatures we know of are simply enacting the plays written in their DNA? If hungry; eat. If tired; sleep. Some people would agree with this point. What then are the implications of a self-aware machine? If a machine were made to be sentient, would it simply enact the plays written in its code, or would it be something greater than its inherent code and processing ability: greater than the sum of its parts?
The common wisdom(which is often anything but) is that if you could create a computer large enough, with enough memory and sufficient processor speed it would suddenly become sentient, and many people view human sentience in this manner: we are simply so smart we can see that we are smart. But is there something else behind sentience?
One theory held by some quantum theorists stated that because in Quantum Theory there are particle "indecision" this must be where humans get their sentience, as our lives are ruled by the decision to do one thing or another. This theory was mostly discarded, and one quote (by someone I cannot unfortunately remember the name of) is "This theory is akin to saying that the Taj Mahal is beautiful because each and every molecule and atom of the Taj Mahal has a tiny piece of beauty in it." which seems to make sense.
Another theory is that sentience arises through super-natural manifestation, the soul for instance. This theory is obviously held by most religeon, and is a fair approximation of saying "the sum of a person is greater than it's parts". To me this theory makes a lot of sense, but I am not religious, and refuse to believe that a "god" made man special, especially since no one (credible) has seen or heard from him in the last two thousand years, and before that who really knows what happened? Maybe Jesus did exist once, but the view we have of him today is probably nothing remotely resembling what he actually was.
Yet another theory of sentience is that is simply a tool used by our genes to ensure our survival, and that WE (the part of us we consider to be us) are simply the tool for making decisions quickly, without needing to know the billions of bits of data flowing around our brains, that as people we do not actually exist other than as a thin cover for our minds: a way of interfacing simply with the world around us.
To me this all seems very daunting, because as I learn more and more about the deep theories of science, all I see around me is confusion. Are we simply the sum of our parts? Are we just vessels for achieving biological and chemical goals? Even as a stubborn atheist, I see that something must be behind sentience, but I am sure that it is purely scientific, a natural phenomenon: I refuse to believe in the super-natural. However, the boundaries of "natural" and "super-natural" are somewhat fuzzy, they are not solid black lines, but a fuzzy blur. Science has proven that particles can travel back in time, that humans can sometimes see things that may seem impossible (remote viewing). No one knows what the scientists of tomorrow will discover, but I am sure of one thing: no matter how far we look we will not see God. | 
