Concept (glossary)
An abstraction; a general idea inferred or derived from specific instances. (Oxford Dictionaries Online 2012)
Source(s)
Oxford Dictionaries Online S.v. "Concept" Accessed February 20, 2012. http://oxforddictionaries.com/definition/concept
Discussion
A concept is an abstraction; a general idea inferred or derived from specific instances. For example, by viewing a pet dog, one can infer that there are other dogs of that “type.” Hence, from this observation (or perhaps a set of observations) the concept of a dog is developed in one's mind. Concepts are bearers of meaning, as opposed to agents of meaning and can only be thought about, or designated, by means of a name.
principles depend on concepts in order to state a “truth.” Hence, principles and concepts go hand in hand; principles cannot exist without concepts and concepts are not very useful without principles to help guide the proper way to act (Lawson and Martin 2008).