Rationality is a word that means to be reasonable, or to make decisions based on sound reasoning, logic, and facts. There are many rationality quotes, and some of these can show just how irrational human beings can be at times. Rationality means to be in a rational state, allowing facts and true information to form the basis for decisions and actions rather than instinct or gut feelings. If you use rationality then you look at all the facts involved and then you make a decision based on the facts, not on what you think or feel. Rationality is a trait that can help you succeed in the world and it can prevent you from making common mistakes. If you do not use rationality then you do not examine the facts, you just make a decision based on what you feel.