Virtually every branch of knowledge, as we know it today, came from particularly two powerful empires of the ancient past, which are the Greek and Roman Empire. Although there were other civilizations, such as the Arabs and the Mayans, that made progress in knowledge, especially mathematics, the Greeks and Romans have been more recognized for the development of other branches of knowledge. The Greeks and Romans have been known to be the promoters of the natural sciences and philosophy. Psychology stemmed from philosophy. Unlike philosophy, however, it encompassed the techniques of the natural sciences. Psychology seemed to be the link between philosophy and the sciences back then.
The main concern of the discipline of psychology in ancient times was the "[speculation of] the nature and locus of the mind, sensation and perception, memory, and learning". There existed a strong connection between psychology and medicine, physiology, and neurology. The purpose of psychology, for the ancient physicians and philosophers, was to describe its procedures and demeanor in terms of science (e.g. medicine). In order to understand the emergence of psychology, the advances in medicine in these ancient cultures must be discussed. That way, one can see how psychology was linked to each one of them, in one way or the other.
Early Greek medicine was more of a divine matter. It was believed that the God Asclepius was the god of medicine. Priests would live at his temples and claimed they knew the ways of healing people. It was not until around 500 B.C., a Greek physician named Alcmaeon began to dissect animals to observe their skeleton, muscles, and brain. This was most probably the first ever to describe a phenomenon through objective observations. Through his observations, he believed that illness was due to an imbalance in the body. This idea prevailed for many centuries in the history of medicine.
Hippocrates succeeded Alcmaeon and rejected the superstitious ideas of priests being the only healers. He founded a medical school and taught his students that since disease came from something natural, it must be treated by natural means. He believed that the body was able to heal itself by the power of healing of nature. Therefore, one was not allowed to interfere with such power. Instead, in order for the body to heal, it must have harmony, and the doctor's task was to maintain such harmony in the patient. This was one of the first approaches in where the doctor's concern was the patient rather than the disease.
Hippocrates made certain neurological discoveries. He concluded accurately that the left hemisphere of the brain controlled the right side of the body and the right hemisphere controlled the left side of the body. In his book, The Art of Healing, he discussed about illnesses, such as paranoia, mania, melancholia, phobias, postpartum depression, and hysteria (all of these illnesses now fall in the category of psychopathology).
He soon came up with a theory related to humors. According to Hippocrates, the body had four humors, which were black and yellow vile, blood, and phlegm. An excess of any of these humors would cause illnesses. He believed that the humors were mightily linked to the personality and temperament of an individual. Excessive black vile indicated a melancholic and irritable personality. Too much yellow vile would be present in individuals who were irate, ill-tempered, and maybe manic. An overflow of phlegm was designated to those who had a dull and indifferent personality. Too much blood in an individual would explain for his/her constant happiness and optimism.
In his most eminent work, De morbu sacro (Concerning the Sacred Disease) discussed about epilepsy, which was believed to occur by divine intervention. Hippocrates disapproved this idea and stated that epilepsy was "a disease caused by the brain's disharmony and predicted that examination of the brain of an...