Much of our mental life is involuntary. For just one example, we can't straightforwardly decide what to believe. Thus if you don't believe p and I offer you a big reward if you start believing p, you can't just do it for the money.

So it's not suprising that we can't stop thinking about X just because we want to. But the desire not to think about X may be worse than ineffective: it may actually be counterproductive. When we think about not wanting to think about X, that brings X to mind, so it sometimes has the opposite of its intended effect.

Harvard psychologist Daniel Wegner has done extremely interesting empirical work on this topic. You can read a summary of his findings here (http://www.wjh.harvard.edu/%7Ewegner/seed.htm).

Wegner’s research suggests that consciously trying to suppress a thought has the ironic consequence of making that thought more rather than less available to our conscious and non-conscious mental processes.

Wegner thinks this happens because mental control rests on two distinct processes – a conscious operating process that works explicitly to suppress the thought in question, and an unconscious ironic process that checks periodically to see whether the operating process is working effectively. This means that while the operating process is busy helping us find other things to think about, the ironic process keeps focusing on the content itself, thereby rendering it accessible.

Wegner thinks that this two-part model can help explain a range of otherwise perplexing mental phenomena – in areas ranging from sports psychology to racist behavior to insomnia.

Interestingly, Wegner’s research seems to suggest that the most effective way to get rid of unwanted thoughts is through a kind of “letting go.” I leave it to panelists who are more familiar with non-Western traditions to say more about how one might go about doing this.