Rubinstein further stressed that Platonism thrives on the idea that human knowledge only becomes pure when it is more abstract; hence, knowledge explicated through concrete terms are considered as transmitted knowledge only, and is not considered the knowledge that humans will truly aspire for, and pursue as a purpose in life. Criticisms against Platonism abound because of its inappropriateness and lack of responsiveness to the realities of human life and experience. Indeed, people cannot strongly subsist to the thought that knowledge in the most abstract form, because knowledge not utilized defeats the very purpose on why knowledge are generated, found, and developed -- to be used for human progress and self-development.

These criticisms against Platonism served as the starting point why utilitarianism became a popular and most subsisted to philosophical thought in the 19th century, and until today. First developed by JS Mill, utilitarianism subsisted to the belief that more than just experiential knowledge, humanity's pursuit for knowledge is actually an attempt to achieve happiness in life -- which Mill interpreted as humanity's way of achieving rationalization, in effect.

In his analysis, Brennan mentioned how "[h]uman excellence...requires the development of capacities and powers...education of the distinct capacities of a human being requires choice, not custom alone" (486). This analysis reflected how utilitarianism is not just an example of experiential knowledge, but it is also a display of free will exercised by the individual, which is the first step towards self-development and -progress, which will eventually lead to the ultimate goal of humanity, which is to promote social progress and development.
Bibliography

Brennan, J. (2005). "Choice and excellence: a defense of Millian Individualism." Social Theory and Practice, Vol. 31, No. 4.

Rubinstein, E. (2006). "The philosophical spirit from Plato to Nussbaum." Commonwealth, Vol. 133, Issue 4.