Free will probably exists in humans.

I agree with my opponent's refinement of my second definition, and accept this as an alternative: "Free will means that the ultimate decision comes down to the rational actor and is not wholly determined by external conditions." The reason I stated that my opponent has burden of proof is that I was thinking that it is not possible to scientifically prove that free will does not exist. After I thought about it I realized that this is not actually true, since if twins were raised in identical conditions and performed the exact same actions, then this would disprove free will (or at least prove it to be very unlikely). I am, however, planning on using logical arguments and not scientific ones. So I accept that I have burden of proof as well as my opponent. In light of this, I request that my opponent forfeit the last round so that we get an even number of posts. "The NEG provides a more far-retched / unreasonable reality (humans are automatons who have no purpose for life other than to reflect the external whims of nature), Occam's Razor demonstrates that the burden of proof rests on the one proposing a more ridiculous assumption." Although this is a side point, I disagree. Things with no free thought are simpler than those with free thought, and the simplest explanation is the most likely. Why Free Will Is Impossible Every event is caused by a preceding event. To our knowledge, events do not happen unless they are caused by a previous event. This works all the way down to the molecular level. If every event is caused by another event, free will is impossible since it is simply the effect of some cause. Even if twins are raised in very similar social factors, chaos theory must be taken into account. There is so much going on within an environment that it is impossible to perfectly replicate with current technologies; even the fact that one twin is born first could significantly affect the outcome of his or her entire life. A single atom moving in a different direction could change everything. "The negative MUST assume, in order for his side to be legitimate, that there is genetic basis for thought." I am not arguing that our choices are entirely dictated by genetics. I am arguing that they are dictated by genetics AND by external and internal factors. Since everything is caused by something else (except for the first cause), each event is dependent on a previous one, and free will is not possible under these circumstances since free will requires independent events. The first cause (whatever it was, or if it even existed) cannot be a source of free will, since there can only be one first cause if we are accepting that everything is caused by something else. But what if we do not accept that everything was caused by something else? An event that is truly independent of every other event is fundamentally unpredictable: if it could be predicted, then it would not be independent. It is therefore random. And randomness is not free will, it is just randomness. Having a set of choices and choosing one randomly is not free will. Having a set of choices and making a choice that is dependent on a previous event is not free will either. As these are the only two possible scenarios, free will is not possible. Because of this, my opponent's arguments are irrelevant.