Super murderers from Alexander and Qin Shihuangdi to Stalin, Hitler, Roosevelt, Truman, and Mao could not happen without participation in or acquiesence to their authoritarian madnesses. When authority is combined with the guru phenomena one gets Pharoahs, Popes, Jim Jones, and David Koresh, none of whom would have had any influence without the support of self-deceived believers. Two sources of beliefs are environment and imagination. The first and primary source of belief is environment with parents playing the pre-eminent role. There is a high statistical probability that children will acquire the beliefs of their parents and maintain them for a lifetime.
Church is another source of belief.
Dictionaries define educate as to persuade to feel, act, and believe in a desired way. Both truth and bullshit can arise from imaginative processes. With imagination you get science, mathematics, and technology. With imagination you also get religious, economic, and political bullshit. Today, what is produced as art and literature is almost wholly commercial product.