What is a Doctrine

Doctrine (Latin: doctrina) is a codification of beliefs or "a body of teachings" or "instructions", taught principles or positions, as the body of teachings in a branch of knowledge or belief system. The Greek analogy is the etymology of catechism.

Often doctrine specifically connotes a corpus of religious dogma as it is promulgated by a church, but not necessarily: doctrine is also used to refer to a principle of law, in the common law traditions, established through a history of past decisions, such as the doctrine of self-defense, or the principle of fair use, or the more narrowly applicable first-sale doctrine. In some organisations, doctrine is simply defined as 'that which is taught', in other words the basis for institutional teaching of its personnel about its internal ways of doing business.

Foreign policy of Doctrine
In matters of foreign policy, a doctrine, also known as dogma, is a body of axioms fundamental to the exercise of a nation's foreign policy. Hence, doctrine, in this sense, has come to suggest a broad consistency that holds true across a spectrum of acts and actions. Doctrines of this sort are almost always presented as the personal creations of one particular political leader, whom they are named after. Examples include the Monroe Doctrine, the Stimson Doctrine, the Truman Doctrine, the Eisenhower Doctrine, the Nixon Doctrine, the Brezhnev Doctrine, the Kirkpatrick doctrine, the Bush Doctrine.

Religious usage
Examples of religious doctrines include:
 * Christian Trinity and virgin birth
 * Roman Catholic transubstantiation and immaculate conception
 * Calvinist predestination
 * Methodist Prevenient Grace
 * Jainism The Doctrine of Postulation or Syādvāda

One department of the Roman Curia is called the Congregation for the Doctrine of the Faith.

Military usage
The term also applies to the concept of an established procedure to a complex operation in warfare. The typical example is tactical doctrine in which a standard set of maneuvers, kinds of troops and weapons are employed as a default approach to a kind of attack.

Examples of military doctrines include:
 * Blitzkrieg of World War II
 * Hit-and-run tactics
 * Shock and Awe
 * Guerre de course
 * Mahanian of late 19th up to mid-20th Century
 * Trench Warfare of World War I
 * Manhunting Doctrine, or Assured Individual Destruction

Almost every military organization has its own doctrine. Sometimes written, sometimes unwritten. Some military doctrines are transmitted through training programmes. More recently, in modern peacekeeping operations, which involve both civilian and military operations, more comprehensive (not just military) doctrines are now emerging such as the 2008 United Nations peacekeeping operations' "Capstone Doctrine" which speaks to integrated civilian and military operations.

Legal usage
A legal doctrine is a body of inter-related rules (usually of common law and built over a long period of time) associated with a legal concept or principle. For example the doctrine of frustration of purpose now has many tests and rules applicable with regards to each other and can be contained within a 'bubble' of Frustration. In a court session a defendant may refer to the doctrine of justification.

It can be seen that a branch of law contains various doctrine, which in turn contains various rules or tests. The test of Non-occurrence of crucial event is part of the doctrine of Frustration which is part of Contract Law. Doctrines can grow into a branch of law; restitution is now considered a branch of law separate to Contract and Tort.

Indoctrination
The term indoctrination came to have awkward connotations during the 20th century, but it is necessary to retain it, in order to distinguish it from education. In education one is asked to stand as much as possible outside the body of accumulated knowledge and analyze it. In indoctrination on the other hand, one stands within the body of knowledge and absorbs its teachings. Compare theology and comparative religion for examples, of which many could be drawn.