please friends, is there any difference between the two? And if there is what are the differences.

The difference between those two is
Reason: Is used to explain phenomenon or events already done or why they should be to be done.

Purpose: Is used to explain intentions, aims, goals and mission of an intending event.

thanks bro.

Thomas Aquinas’ Notion of Reason and Morality as a Panacea to Religious Crisis in Nigeria

Thomas Aquinas cannot be said to be the only philosopher who has treated the notion of reason and morality. Some philosophers before and after him have also written on this matter, though, from different points of view. This chapter, therefore, seeks to x-ray the views of some philosophers on morality and reason,

http://www.scharticles.com/thomas-aquinas-notion-of-reason-and-morality-as-a-panacea-to-religious-crisis-in-nigeria/