ABSTRACT
Henri Poincaré was a French mathematician and physicist. His key contributions to these scientific fields rest upon a foundation comprised his personal life and social milieu. These scientific contributions are further supplemented by his own reflections over psychological (mainly cognitive) aspects of his scientific process culminating in unique contributions in the domain of philosophy of science. In addition to the usual inductive and deductive dimensions of the cognitive process, Poincaré emphasizes the importance of the intuitive. Further, in addition to the Category of hypotheses that is Refutable or irrefutable, he emphasizes the category of hypotheses that despite being neither refutable nor irrefutable is, nevertheless, indispensable. This chapter is therefore organized to look at Poincaré sequentially as the person, the scientist, the psychologist, and the philosopher of science.
