In generative philosophy of cognitive sciences and evolutionary psychology, free will is assumed not to exist. However, an illusion of free will is created, within this theoretical context, due to the generation of infinite or computationally complex behaviour from the interaction of a finite set of rules and parameters. Thus, the unpredictability of the emerging behaviour from deterministic processes leads to a perception of free will, even though free will as an ontological entity is assumed not to exist. In this picture, even if the behavior could be computed ahead of time, no way of doing so will be simpler than just observing the outcome of the brain's own computations.
As an illustration, some strategy board games have rigorous rules in which no information (such as cards' face values) is hidden from either player and no random events (such as dice-rolling) occur in the game. Nevertheless, strategy games like chess and especially Go, with its simple deterministic rules, can have an extremely large number of unpredictable moves. By analogy, "emergentists" suggest that the experience of free will emerges from the interaction of finite rules and deterministic parameters that generate infinite and unpredictable behaviour. Yet, if all these events were accounted for, and there were a known way to evaluate these events, the seemingly unpredictable behavior would become predictable.
Cellular automata and the generative sciences model emergent processes of social behavior on this philosophy, showing the experience of free will to be a gift of ignorance or a product of incomplete information.
That was the weirdest display of geekdom that I have ever seen in my entire life.
Determinism is a broad term with a variety of meanings. Corresponding to each of these different meanings, there arises a different problem of free will.
Causal (or nomological) determinism is the thesis that future events are necessitated by past and present events combined with the laws of nature. Such determinism is sometimes illustrated by the thought experiment of Laplace's demon. Imagine an entity that knows all facts about the past and the present, and knows all natural laws that govern the universe. Such an entity might, under certain circumstances, be able to use this knowledge to foresee the future, down to the smallest detail.
Logical determinism is the notion that all propositions, whether about the past, present or future, are either true or false. The problem of free will, in this context, is the problem of how choices can be free, given that what one does in the future is already determined as true or false in the present.
Theological determinism is the thesis that there is a God who determines all that humans will do, either by knowing their actions in advance, via some form of omniscience or by decreeing their actions in advance. The problem of free will, in this context, is the problem of how our actions can be free, if there is a being who has determined them for us ahead of time.
Biological determinism is the idea that all behavior, belief, and desire are fixed by our genetic endowment. There are other theses on determinism, including cultural determinism and psychological determinism. Combinations and syntheses of determinist theses, e.g. bio-environmental determinism, are even more common.
*sigh*
That was the weirdest display of geekdom that I have ever seen in my entire life.
Compatibilists maintain that determinism is compatible with free will. A common strategy employed by "classical compatibilists", such as Thomas Hobbes, is to claim that a person acts freely only when the person willed the act and the person could have done otherwise, if the person had decided to. Hobbes sometimes attributes such compatibilist freedom to the person and not to some abstract notion of will, asserting, for example, that "no liberty can be inferred to the will, desire, or inclination, but the liberty of the man; which consisteth in this, that he finds no stop, in doing what he has the will, desire, or inclination to doe." In articulating this crucial proviso, David Hume writes, "this hypothetical liberty is universally allowed to belong to every one who is not a prisoner and in chains". To illustrate their position, compatibilists point to clear-cut cases of someone's free will being denied, through rape, murder, theft, or other forms of constraint. In these cases, free will is lacking not because the past is causally determining the future, but because the aggressor is overriding the victim's desires and preferences about his own actions. The aggressor is coercing the victim and, according to compatibilists, this is what overrides free will. Thus, they argue that determinism does not matter; what matters is that individuals' choices are the results of their own desires and preferences, and are not overridden by some external (or internal) force. To be a compatibilist, one need not endorse any particular conception of free will, but only deny that determinism is at odds with free will.
That was the weirdest display of geekdom that I have ever seen in my entire life.
"Modern compatibilists", such as Harry Frankfurt and Daniel Dennett, argue that there are cases where a coerced agent's choices are still free because such coercion coincides with the agent's personal intentions and desires. Frankfurt, in particular, argues for a version of compatibilism called the "hierarchical mesh". The idea is that an individual can have conflicting desires at a first-order level and also have a desire about the various first-order desires (a second-order desire) to the effect that one of the desires prevail over the others. A person's will is to be identified with her effective first-order desire, i.e., the one that she acts on. So, for example, there are "wanton addicts", "unwilling addicts" and "willing addicts." All three groups may have the conflicting first-order desires to want to take the drug to which they are addicted and to not want to take it. The first group, "wanton addicts", has no second-order desire not to take the drug. The second group, "unwilling addicts", has a second-order desire not to take the drug, while the third group, "willing addicts", has a second-order desire to take it. According to Frankfurt, the members of the first group are to be considered devoid of will and therefore no longer persons. The members of the second group freely desire not to take the drug, but their will is overcome by the addiction. Finally, the members of the third group willingly take the drug to which they are addicted. Frankfurt's theory can ramify to any number of levels. Critics of the theory point out that there is no certainty that conflicts will not arise even at the higher-order levels of desire and preference. Others argue that Frankfurt offers no adequate explanation of how the various levels in the hierarchy mesh together.
That was the weirdest display of geekdom that I have ever seen in my entire life.
In Elbow Room, Dennett presents an argument for a compatibilist theory of free will, which he further elaborated in the book Freedom Evolves. The basic reasoning is that, if one excludes God, an infinitely powerful demon, and other such possibilities, then because of chaos and quantum randomness, the future is ill-defined for all finite beings. The only well-defined things are "expectations". The ability to do "otherwise" only makes sense when dealing with these expectations, and not with some unknown and unknowable future. Since individuals have the ability to act differently from what anyone expects, free will can exist. Incompatibilists claim the problem with this idea is that we may be mere "automata responding in predictable ways to stimuli in our environment". Therefore, all of our actions are controlled by forces outside ourselves, or by random chance.
That was the weirdest display of geekdom that I have ever seen in my entire life.
Another argument for incompatibilism is that of the "causal chain." Most incompatibilists reject the idea that freedom of action consists simply in "voluntary" behavior. They insist, rather, that free will means that man must be the "ultimate" or "originating" cause of his actions. He must be a causa sui, in the traditional phrase. To be responsible for one's choices is to be the first cause of those choices, where first cause means that there is no antecedent cause of that cause. The argument, then, is that if man has free will, then man is the ultimate cause of his actions. If determinism is true, then all of man's choices are caused by events and facts outside his control. So, if everything man does is caused by events and facts outside his control, then he cannot be the ultimate cause of his actions. Therefore, he cannot have free will.
That was the weirdest display of geekdom that I have ever seen in my entire life.
~Commander of the LG15 Defense Force
I'm Kristin, but you can call me Kris. 
*hugs*
