Final answer:
David Wechsler was an influential figure in clinical psychology, who developed important intelligence scales that broadened the understanding of intelligence to include verbal and nonverbal skills.
Step-by-step explanation:
David Wechsler is a prominent figure in the history of clinical psychology, known for his development of several intelligence scales, such as the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Intelligence Scale for Children (WISC). His work diverged from the then-dominant Binet scales by including a broader concept of intelligence, consisting of both verbal and nonverbal (or performance) skills. Wechsler's contribution significantly shaped the assessment of cognitive abilities and the diagnosis of intellectual disabilities, influencing psychoeducational assessments and educational planning.