Edward Lee Thorndike (1874-1949) was a distinguished American psychologist whose work significantly influenced the development of educational psychology in the early 20th century. A prominent figure in the transition from introspective psychology to behaviorism, Thorndike is well-known for formulating the Law of Effect - a principle central to the theories of learning and conditioning. Thorndike's scholarship extended beyond learning theory, encompassing various facets of psychology. His publication, 'The Psychology of Arithmetic' (1922), exemplifies his dedication to understanding the cognitive processes behind education, particularly the learning and teaching of mathematics. An advocate for empiricism in educational practices, Thorndike's legacy persists through his influence on standardized testing and instructional design. A graduate of Wesleyan University, Harvard, and Columbia, where he earned his Ph.D., Thorndike was a prominent part of the intellectual milieu of his time. He held a long-time professorship at Teachers College, Columbia University, shaping generations of educators and theorists. His scholarly approach often combined a rigorous scientific method with a practical understanding of the educational environment, thus briditing theoretical psychology with real-world application. His extensive bibliography includes works such as 'Animal Intelligence' (1898), 'Education: A First Book' (1912), and 'The Measurement of Intelligence' (1927), attesting to his prolific and diverse contributions to the field.