“Following the thoughts of a great man,” wrote A. S. Pushkin, “is the most entertaining science.” Aphorisms of famous thinkers and scientists, politicians and writers, poets and artists are rightfully not only a source of worldly wisdom, but also answers to eternal questions that concern many generations of people. Knowledge for a person is a kind of guide, a guide that allows one to navigate the world around us and helps to comprehend it. However, knowledge is multifaceted and unpredictable, and in the hands of an ignorant person it can turn into a terrible weapon. The eternal confrontation between knowledge and ignorance is an inexhaustible source of thought.