I believe the most significant concept I learned from psychology is cognitive economy. Cognitive economy is the short-cut for us to mobilize as less resource in mind as possible to solve the problem. It is one of the most adaptive abilities possessed by human beings. If I can be sure about the answer at an 80% confidence level within few minutes, why should I bother to spend another one hour to demonstrate that it is 100% true? Instead, I can apply the extra one hour to do other tasks and make my life more efficient and colourful, such as inventing a machine, sending someone to the moon and so on. Although sometimes cognitive economy encounters difficulties on the reliability, overall it efficiently meets our needs on daily life. On fields requiring high level of accuracy, we have computers to work on these non-creative and time-consuming tasks.
Furthermore, cognitive economy also motivates creative activities. For we are misers on thinking, it is so boring for us to do the same thing time after time. So we just apply tools and invent machines to save our time and energy on reasoning. For me now, there is no need to worry about any spelling errors in this post. The word software itself corrects the errors.