This document discusses intelligence and different theories about what constitutes intelligence. It provides brief biographies of theorists like Theodore Simon, Jean Piaget, Lev Vygotsky, and David Wechsler who contributed to the study and testing of intelligence. The document defines intelligence as the ability to acquire and apply knowledge. It also discusses Howard Gardner's theory of multiple intelligences, which proposes there are different types of intelligences including linguistic, logical-mathematical, spatial, bodily-kinesthetic, musical, interpersonal, and intrapersonal. The document encourages students to recognize their strengths in different types of intelligences.