A Study of the Phenomena of Suffering and Happiness in Visuddhimaggo The Rationale and Significance of the Research Nature, says Bentham, has placed mankind under the governance of two severing masters, pain and pleasure. These principles determine to a large extent the course of action and thought we adopt in our life. All men endeavor and try to achieve that which is beneficial, good or cause of happiness and try to prevent the happening mischief, pain, evil or unhappiness. But they are not always successful because happiness and the causes of happiness are not known to them. The teaching of Lord Buddha becomes significant from this point of view. The Four Noble Truths are treated as essential elements of the teachings of Buddha by almost all the traditions of Buddhism. The founder of Neo-Buddhism sect in India, Dr. B.R.Ambedkar (1891-1956) does not take them as such. According to him, it makes Buddhism pessimistic and totally other worldly. Lord Buddha was a practical man and his teachings have meaning for common men. Social injustice and economic injustice are the root causes of the unhappiness of commonmen. Buddhism glorified the doctrine of action in order to protest against the doctrines of those who advocated the superiority of one man over other on the ground of birth in high family. A vivid picture of glorification of action can be found in one of the oldest works-Suttanipāta. Buddhism has very much meaning for present conditions of the world as it teaches the doctrine of peaceful co-existence of all humanbeings. It is very difficult to accept the view of Dr. Ambedkar in presence.