This chapter attempts to analyze what people thought about curiosity at different times, how it was perceived by philosophers, and later also by educators, including teachers with practical experience in mathematics education. We examine certain historically important textbooks in mathematics as well as techniques by means of which authors endeavored to awaken and sustain curiosity. The concept of curiosity turns out to be connected with the concept of human individuality, attitudes toward which went through significant transformations. Attitudes toward curiosity in mathematics and its study also changed over time: what might provoke curiosity could be understood in different ways.