It refers to a law or rule, which is enforced, which must be governed to achieve a purpose at the end; this being the consequence of something. In which natural laws, for example, we speak of physical principles, as in other fields the existence of the principle is necessary that must be fulfilled or are the result of different facts. Legally speaking, the academy of the Spanish language defines it in several ways, a base, a foundation, an origin, a fundamental reason for something or about something, the first moment of being, the existence of life, a guide, between others.
The concept that can be understood, as a discipline, being the reflection or primordial characteristic of a system, which is assumed, that without which it is not possible to advance, work, live, understand a specific system. The word comes from the old Latin, Principium, which in its etymology of the word is, what is taken first. Also related is the principle with morality and good customs, of a person, group or society, which in religion are based on this for a morality full of honor; since a double morality or a doubtful morality, is not on the foundations of some honest principles, when it is established as an individual conscience, which leads to an ethic of valuesobliged of what is or should be done as correct. The principle of utility is taken as a cause of action for a purpose, to achieve the objectives that must be exercised to reach a desired goal.