You throw out all your existing DNA and get a new batch. How people think is determined, to a very large extent, by their DNA. (For example, I have always tended to think logically it just comes naturally - and can usually set emotions aside. That's obvious from the posts I make.) So you probably won't be able to make fundamental changes to the way you think. However, if you practice, you may be able to make some changes. I'm no expert on this topic, but perhaps you could think about some of the issues you have been thinking about, try to figure out why you thought about them the way you did, and then consider other ways in which it would have been possible to think about them. It may be easier if you start with fairly, unimportant issues, where the stakes are not high. That sort of introspection may give you some clues about how you can introduce a bit more logic and rationality into your thinking. Good luck.