Picture: Marta Diaz

Definition of Law
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In a stricter and more exact sense law is spoken of only in reference to free beings endowed with reason. But even in this sense the expression law is used sometimes with a wider, sometimes with a more restricted meaning.

By law are at times understood all authoritative standards of the action of free, rational beings. In this sense the rules of the arts, poetry, grammar, and even the demands of fashion or etiquette are called laws.

This is, however, an inexact and exaggerated mode of expression. In the proper and strict sense laws are the moral norms of action, binding in conscience, set up for a public, self-governing community.

This is probably the original meaning of the word law , whence it was gradually transformed to the other kinds of laws (natural laws laws of art). Law can in this sense be defined with St. Thomas Aquinas(Summa Theologica I-II:90:4) as: A regulation in accordance with reason promulgated by the head of a community for the sake of the common welfare.