modern compatibilists in psychology have tried to revive traditionally accepted struggles of free will with the formation of character. Compatibilist free will has also been attributed to our natural sense of agency, where one must believe they are an agent in order to function and develop a theory of mind. The notion of levels of decision is presented in a different manner by Frankfurt. Frankfurt 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 prevails over the others. A person's will is identified with their effective first-order desire, that is, the one they act on, and this will is free if it was the desire the person wanted to act upon, that is, the person's second-order desire was effective. 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 they are addicted to and to not want to take it. The first group, wanton addicts, have no second-order desire not to take the drug. The second group, "unwilling addicts", have a second-order desire not to take the drug, while the third group, "willing addicts", have a second-order desire to take it. According to Frankfurt, the members of the first group are devoid of will and therefore are 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 they are addicted to. 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. Free will as unpredictability 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 epistemic limits on the precision of our knowledge of the