Determinism is self-defeating

Thank you ConformistDave for accepting my challenge. I look forward to an interesting debate. I am fine with SEP's definition of determinism, and so I will proceed to make my case. Premise 1: If determinism is true, then each person's beliefs have been pre-determined. Determinism, as defined by Con, entails that every event that occurs is necessitated by antecedent events and conditions in accordance with the laws of nature. This means that when an individual comes to a conclusion after examining the evidence pertinent to an issue (such as determinism), their coming to this conclusion was necessitated; that is, it had to occur. Thus, if causal determinism is true, my belief that determinism is self-defeating was in the works all along, and I could not have not come to this conclusion because my choice to reject determinism was necessitated by prior events (which were themselves necessitated by prior events, and so on). If I later change my mind, this will also have been necessitated, and have been in the works all along. Premise 2: If a person's beliefs have been pre-determined, then they are not held rationally. As stated under premise 1, if determinism is true, then any beliefs a person has have been necessitated by previous events, which have themselves have been necessitated by previous events, and so on. Thus, all choices are simply events in a great cosmic machine which operates according to the laws of nature. An evaluation of any event within the machine will itself have been determined by the the laws of nature. This poses a problem for the possible of any rational evaluation of one's beliefs. One cannot rationally evaluate if causes have lined up to give one rational beliefs, because an evaluation of the causes is itself necessitated by causes which may or may not have worked in one's favor. (And in any case, most of us to not have time to examine all the relevant chemical reactions in our brains when we make decisions.) To hold an belief rationally, or to rationally evaluate one's beliefs, there must be the possibility - at least in some cases - of being able to freely choose to evaluate the evidence in an objective way. One must be able to "step outside" the machine in order to evaluate anything within it - such as scientific data. (This does not guarantee that one will always get true beliefs after freely choosing to look at the evidence. In science, for example, theories are always changing in order to deal with new data. However, knowing when a theory is no longer sufficient, or when it has been proven false, requires rationality). Premise 3: An argument for causal determinism presupposes rationality. The person who argues for determinism must believe that they are making a rational argument and logically proceeding from premises to a valid conclusion, or that all of the relevant scientific data support their point. Premise 4: Therefore determinism is self-defeating. Since arguments for determinism presuppose rationality (like all arguments), but determinism itself undermines the possibility of rationality, I conclude that determinism is a self-defeating argument. I have endeavored to express myself as clearly as possible, and I hope that all of my points are accordingly intelligible. I look forward to hearing Con's reply.