Psychology is the science of mind and behavior. Its immediate goal is to understand humanity by both discovering general principles and exploring specific cases. For many practitioners, one goal of applied psychology is to benefit society. In this field, a professional practitioner or researcher is called a psychologist, and can be classified as a social scientist, behavioral scientist, or cognitive scientist. Psychologists attempt to understand the role of mental functions in individual and social behavior, while also exploring the physiological and neurobiological processes that underlie certain functions and behaviors.
Psychologists explore such concepts as perception, cognition, attention, emotion, phenomenology, motivation, brain functioning, personality, behavior, and interpersonal relationships. Some, especially depth psychologists, also consider the unconscious mind.a Psychologists employ empirical methods to infer causal and correlational relationships between psychosocial variables. In addition, or in opposition, to employing empirical and deductive methods, some—especially clinical and counseling psychologists—at times rely upon symbolic interpretation and other inductive techniques. Psychology incorporates research from the social sciences, natural sciences, and humanities.
While psychological knowledge is typically applied to the assessment and treatment of mental health problems, it is also applied to understanding and solving problems in many different spheres of human activity. Although the majority of psychologists are involved in some kind of therapeutic role (clinical, counseling, and school positions); many do scientific research on a wide range of topics related to mental processes and social behavior (typically in university psychology departments) and/or teach such knowledge in academic settings; and some are employed in industrial and organizational settings, and in other areas such as human development and aging, sports, health, the media, law, and forensics.
The word psychology literally means, "study of the soul" (ψυχή, psukhē, meaning "breath", "spirit", or "soul"); and "-λογία" (-logia, translated as "study of" or "research"). The Latin word psychologia was first used by the Croatian humanist and Latinist Marko Marulić in his book, Psichiologia de ratione animae humanae in the late 15th century or early 16th century. The earliest known reference to the word psychology in English was by Steven Blankaart in 1693 in The Physical Dictionary which refers to "Anatomy, which treats of the Body, and Psychology, which treats of the Soul."
The study of psychology in a philosophical context dates back to the ancient civilizations of Egypt, Greece, China, India, and Persia. Historians point to the writings of ancient Greek philosophers, such as Thales, Plato, and Aristotle (especially in his De Anima treatise), as the first significant body of work in the West to be rich in psychological thought.
German physician Wilhelm Wundt is credited with introducing psychological discovery into a laboratory setting. Known as the "father of experimental psychology," he founded the first psychological laboratory, at Leipzig University, in 1879. Wundt focused on breaking down mental processes into the most basic components, starting a school of psychology that is called structuralism. Edward Titchener was another major structuralist thinker.