"The Psychology of Arithmetic" is a book written by the eminent psychologist Edward Lee Thorndike. In this work, the author examines the psychological aspects of the process of learning and using arithmetic operations. Thorndike reveals important principles of the mental processes that occur in the brain during the performance of mathematical tasks. The book "Psychology of Arithmetic" is an important scientific document in the field of psychology of mathematics, which helps to understand how a person perceives, processes and uses numerical information. Readers will find in this book not only a theoretical analysis, but also practical advice on optimizing the process of teaching mathematics and developing mathematical skills. So "Psychology of Arithmetic" is not only a research work, but also a practical guide for everyone who is interested in the psychology of mathematics and the pedagogy of mathematics education.