All four definitions of Health are necessary for developing an accurate assessment of one’s overall health and its relation to the presence and absence of known and unknown diseases. This would allow for the development of preventive measures, early detection, and the treatment of health disorders and their complications. Also, a person’s well-being or disability status can be influenced by the presence of mental illness. It is essential for persons who have a mental illness to receive medical attention promptly, even if the illness has been cured or has mainly been resolved. Thus, we can say that all the four Health perspectives – physical, psychological, social, and life-course – play essential roles in defining good health.