Undergraduate / Dean's Scholars Transfer Essay (UT) - a rational process and belief [4]

I have to write an essay to transfer to DS due in a few days, and I'm having a hard time coming up with a topic. Any suggestions/ideas/your own personal ideas would be helpful for me to come up with something of my own.

The topic is:

Explain a belief you accepted at some time in your life but have rejected on the basis of a rational process. Perhaps the change was initiated by something you heard or some experience you have had. For this essay you must go beyond reporting what you heard or describing what happened to you. You must display the process of reasoning that carried you to your new belief. In your essay, be careful to explain the belief itself, reasons you had for holding it, and, most importantly, the rational process that led you to reject it.