Well, either you're a materialist or a dualist (not duelist for you war freaks)
Materialism means that you believe in nothing that is not matter, and by extension you believe that everything can be measured, tested and predicted. Therefore there is no free will, life can have no meaning, and everything that can and will happen has already been decided on from the point of the big bang, which may have been fated by something else. Essentially, by not believing in a "soul" or immaterial part of the body, you must by extension believe that there is no free will, but it is a convenient and very appealing myth to believe in. This also implies no belief in religion, or agnosticism, and many materialists take up an arrogant point of view on this subject which is mostly irrelevant, but tends to give atheism a bad name, though many are also respectful about it, because they understand that there is no proof for either side of the dualism/materialism debate, and that there is no proof for or against the existence of a superior power or being, or consciousness, they simply believe that there is nothing out there. That is a very quick breakdown of the materialist camp.
Dualism implies that you believe that to be human must mean that there is more then just the material essence of a body, therefore something immaterial must be part of us as well, commonly called a soul. This is a dualist's explanation for free will, and the absence of fate. They may also believe in a greater power then ourselves, or at the very least accept an agnostic point of view, which is accepting that we know next to nothing, and by that virtue, rejecting and accepting at the same time all types of theistic views that do not suggest something unreasonable. This concept means that if something is known to be true, it is not acceptable to believe otherwise, but if something cannot be proven, it is acceptable to believe something about it, as long as you do not try to pass off your beliefs as truth, since doing so would imply that you had knowledge that is impossible to gain, and by that logic, you would be lying. Another camp of dualism is the religious part, which, although in name is the same as the agnostic/free will camp, is very different, and doesn't require a further explanation.
So, once you've figured out whether you believe in free will or not, then here are your answers for where inspiration comes from.
Materialist: Chemicals in the brain fire at different rates due to minor fluctuations in heat, and thus produce new electronic patters that define what we so foolishly believe is an independent thought.
Dualist: Our immaterial self, which has the inherent ability to use reason and interpret emotion and the senses, creates something new and useful based on what we perceive, and then decides on what to do, based on a concept of free will. The results are that the brain patters will appear the same as in the materialist case, but the source is now something that is able to bring new things in to the material world.
Now, since there is no proof pointing towards either side, one may say that it is a more intelligent approach to go with a materialist side, but they would be wrong. The more intelligent approach here is to accept the possibility of both sides being right, and to base your actions and responses on what is pragmatically effective. Do what you want to do, and feel how you want to feel, and be inspired how you want to be inspired, because even if it's just fate from changes in heat, it won't change what we do or how we think.
/end long essay thing
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