The way Rand and Peikoff use it in their books is extremely vague; how can one practically use his faculty of reason? And what relations does the faculty have in terms of emotions?
The epistemology of objectivism states that man first senses, then he perceives, at which he then gains concepts. Perceptions are merely collections of sensations - that is, all existents are different, it is the stage where a conscious being "identifies". From this, a unit of measure can be obtained from the perceptions to which that unit becomes a concrete concept which man decides to express in symbols. Where is 'reason' in this process? How can I consciously use 'reason' over emotion, and why does emotion conflict with 'reason'?