A rationalist, as I use the word, is a man who attempts to reach decisions by argument and perhaps, in certain cases, by compromise, rather than by violence. He is a man who would rather be unsuccessful in convincing another man by argument than successful in crushing him by force, by intimidation and threats, or even by persuasive propaganda.
Karl Popper (2014). “Conjectures and Refutations: The Growth of Scientific Knowledge”, p.557, Routledge