Some people have to believe that there is such a thing as free will, but I choose not to believe it.
He was joking. Those that believe in free-will have no choice but to believe. He, on the other hand, chooses to believe there isn't.
Well, yes, it is a joke, but there is a real point. Because our brains are modular, different modules of the brain "vote" on our decisions. These modules constitute what Freud called the "subconcious".
We know from dynamic imaging studies of the brain that we make our decisions, and only then do we rationalize them. Since the modules involved in making the decisions are based on association, analogies or symbols (Sometimes a cigar is
not just a cigar!) that really have little or nothing to do with rational decision making, the reasons that our rational minds give as explanations for our decisions are often not the real reasons.
We can make decisions based on emotional associations that we may not even be aware of, based on events that we don't want to remember.
If we do not examine our decisions rationally and honestly, then we really have no free will. Free will can only arise when we examine our decisions and measure them against the objective reality, and not just pass on the unexamined and often irrational associations of the subconscious mind.
There are people on these very forums, (Not to name names!) who are proudly irrational. They base their decisions on their emotional responses which arise from events and patterns in their lives too terrifying, shameful or humiliating to be admitted even to themselves. This they are pleased to call "faith".
One of the symptoms of this form of dementia is the proud boast that they can "choose" what to believe in the face of contradictory evidence, reason or even mathematics. Before they can free themselves they would have to confront the fact that they have publicly shown themselves to be fools, basing their "decisions" on fear and shame that they dare not admit to themselves.
So, such person "have to believe in free will" because they cannot confront the real reasons for their totally constrained "decisions".
By pitiless self-examination one can become aware of one's real reasons, and overide the subconscious process, training the mind to make decisions based upon present realities rather than terrifying, shameful, and humiliating memories that the conscious mind is too fearful to confront.
Thus "free will" is possible, but it is not the default condition, and you usually need not consider it when dealing with people.
That is why I say, "Some people have to believe that there is such a thing as free will, but I choose not to believe it." It is not
just a joke!
(It is amazing that Freud realized this while unaware of the the neurological modularity of the brain, just as Darwin formed his theory without knowing about genetics.)
