Many have wondered whether people believe in free will because of wishful thinking. Often, this is explained with respect to the present and future: if we don't have free will, then we are now like slaves, and are powerless to alter the course of our lives.
I wondered, though, whether wishful thinking might also explain beliefs about free will relative to the past. That is, people who are proud of their past will want to take ownership of it. They will want to believe that they exercised free will to create and fashion their past.
And, interestingly, people who are not proud of their lives will not want to take ownership of their lives. They will want to deny that they have free will. Instead, they'll view their lives as something thrust upon them - that they are passive passengers on an unfortunate ride.
There is a similar effect already known in psychology: people attribute positive events to their disposition, but negative events to their situation.
To test my hypothesis, and to repeat the psychology result with explicit reference to beliefs in "free will", I ran the following experiment. I created an online survey and paid subjects 25 cents each to answer the survey. The survey asked two simple questions:
1. How sure are you that people have "free will" (1-10)?
2. Looking back on your life, how happy are you with the way that your life went (1-10)?
For the first 88 subjects (the survey is ongoing), I've found a correlation (r) of .239, which provides some support for my hypothesis. Happy people tend to believe in free will. Unhappiness will make you more skeptical. There are actually a variety of ways in which the effect may occur. But, as described above, I suspect that people adopt these beliefs out of convenience: if your life turned out poorly, you won't want to believe that you have free will.
The more fascinating question, for me, is whether this result creeps into beliefs about personal identity. Dennett said that incompatibilists have too small a notion of personal identity (e.g. a Cartesian point). Why? Are they unhappy with the larger aspects of themselves? Their genetics? Their childhood? Do they disown these aspects of themselves, shrinking until they are just a point? As Smilansky said, we are merely the unfolding of the given.