The document discusses two major perspectives in clinical psychology - the biological perspective and the cognitive behavioral perspective. The biological perspective views psychological issues through studying the physical basis for animal behavior and human behavior. It involves examining the brain, immune system, nervous system and genetics. The perspective emerged in the early 1800s and is based on the idea that every mental illness has an underlying biological or medical cause. The cognitive behavioral perspective emerged in the early 1900s. It focuses on how human thought processes impact behavior, as a reaction to the mechanistic nature of behaviorism. Theorists under this perspective treat thoughts as behaviors rather than just overt actions. Pioneers included Dollard and Miller who emphasized cognitive concepts to explain abnormal