Wilhelm Wundt was the first person to claim the title of psychologist and to separate psychology from philosophy and science. Considering that Wundt built the first psychology laboratory in 1879 (Schultz & Schultz, 2011), it would appear that psychology is a fairly modern science dating back less than two hundred years. However, considering that psychology has roots in both philosophy and physiology, its foundations extend much further. In this article, I will highlight the contributions of a philosopher and a physiologist and how they contributed to psychology as we know it today. John Locke (1632-1704) was a physician and philosopher (Schultz & Schultz, 2011). Locke authored many works, but his most important contribution to the world of psychology is An Essay Concerning Human Understanding. I chose LockePhilosophers have focused over time on ideas and experiences and how they shape people. Physiology is interested in the body, mainly through observation. Psychology encompasses both of these areas. It is the study of the mind and its processes. This requires us to examine both the physical matter of the body and brain, as well as non-visible thoughts and emotions. John Locke founded empiricism. Empiricism was important in early psychology because it helped found behaviorism. In behaviorism, behavior is the result of a stimulus. Whatever experience the brain has, it can be reconditioned with new stimuli. This theory was introduced by John B. Watson (Schultz & Schultz, 2011) and further developed by BF Skinner and others in neo-behaviorism. Even Pavlov's dogs were an experiment in behaviorism. Ernst Weber's contribution to the beginnings of psychology proved that certain aspects are quantitative or measurable. Without the belief in real results from a physical point of view, Wundt would not have needed to construct the first psychological model.