Ivan Pavlov developed classical conditioning, famously demonstrated when dogs salivated at a bell (conditioned stimulus) associated with food. B.F. Skinner developed operant conditioning, Freud developed psychoanalysis, and Jung developed analytical psychology.
Psychology is the science of the mind and of behavior - the rigorous, systematic attempt to understand why human beings think the way they think, feel the way they feel, and act the way they act. It is a discipline that sits at the fascinating intersection of biology, philosophy, sociology, and medicine, drawing on all of these to illuminate the invisible inner world that shapes everything we do. To understand psychology is, in a very meaningful sense, to understand yourself and the people around you more deeply, more accurately, and more compassionately. The history of psychology is a rich narrative of brilliant insights, controversial theories, and ongoing discovery. In the late nineteenth century, Ivan Pavlov - a physiologist studying digestion in dogs - made one of the most consequential accidental discoveries in the history of science: he noticed that his dogs had begun to salivate not just at the sight of food, but at the sound of his footsteps in the hallway, because they had learned to associate his arrival with feeding. This observation led to the systematic investigation of classical conditioning - the process by which organisms learn to associate a neutral stimulus with a meaningful one - and transformed our understanding of how experience shapes behavior. A few decades later, the American psychologist B.F. Skinner built on this foundation with his concept of operant conditioning, demonstrating that behavior is shaped not only by what precedes it, but by what follows it: rewards strengthen behavior, while punishments suppress it. Meanwhile, Sigmund Freud was constructing an entirely different framework - one that located the driving forces of human behavior not in observable stimuli and responses, but in the churning depths of the unconscious mind, in hidden desires, repressed memories, and the complex dynamics of early childhood relationships. Though many of Freud's specific theories have been revised or rejected by modern research, his fundamental insight - that much of what drives us operates below the level of conscious awareness - remains enormously influential. This quiz explores these and many other fundamental concepts in psychology: cognitive dissonance, the bystander effect, confirmation bias, the placebo effect, Maslow's hierarchy of needs, the stages of grief, and the fight-or-flight response. Each concept opens a window onto a different aspect of the extraordinary complexity of human mental and emotional life. Whether you are a psychology student, a healthcare professional, or simply someone who wants to understand yourself and others better, these insights have the power to change how you see the world.