Principle

A principle is a fundamental truth or a proposition. It serves as the foundation for a system of beliefs or a chain of reasoning. These ideas act as a guide for behavior or evaluation. Principles can make abstract values explicit. They do this by expressing values as specific rules and standards. This process allows values to be operationalized in policy statements and actions.

Without these principles, the effective operation of a system might be impossible.

Principles function at different levels of importance. Some are called operational principles, which include what thinkers call "first principles." Others are higher-order "guiding" or "exemplary" principles. These include ideas like equality, justice, and sustainability. Higher-order principles are also known as superordinate principles. They provide a basis for resolving differences. They help people build agreement and alignment within a group. A system might even be implemented through a specific document of principles. For example, IBM used a document called the 360/370 Principles of Operation.

In the field of law, principles represent values that orient society. They inspire the written norms that organize life under an authority, such as the State. The law establishes a legal obligation in a coercive way. This acts as a principle that conditions action and limits individual liberty. There are many types of legal principles. These include the territorial principle and the homestead principle. Another important one is the precautionary principle. In ethics, the idea of fairness serves as a principle for conduct.

Moral principles guide how people act in a society. To "act on principle" means to act according to one's moral ideals.

People often absorb these principles during childhood through socialization. Some exemplary moral principles include the Golden Rule. Another is the Doctrine of the Mean. The instruction to "first, do no harm" is also a famous example. History shows the weight of these ideas. The philosopher Socrates chose to face execution rather than betray his moral principles.

Science uses principles to define the essential characteristics of a system. These principles can reflect a system's designed purpose. Archimedes' principle is a famous early example. It relates buoyancy to the weight of displaced water. In biology, the central dogma is a key principle. Biologists also use the principle of priority and the principle of Binomial nomenclature for naming species.

Sigmund Freud wrote about the reality principle. This principle helps keep the id and the pleasure principle in check.

Many principles exist in physics and mathematics. Physics includes the principle of least action. Cosmology observes the mediocrity principle and the anthropic principle. It also uses the principle of relativity and the cosmological principle. In quantum mechanics, scientists study the uncertainty principle. Mathematics features the pigeonhole principle and the superposition principle. Even population studies involve principles, such as the Malthusian principle. These rules help scientists organize and understand the natural world.

Logic relies on fundamental principles to establish truth. The principle of sufficient reason states that every event has a rational explanation. This means if an entity exists, there is a reason why it exists. The principle of non-contradiction was discussed by Aristotle.

It states that a thing cannot belong and not belong to itself at the same time. For instance, it cannot rain and not rain in the same place at once. Finally, the principle of excluded middle, or "tertium non datur," is a law of thought. It states that either a proposition is true or its denial is true. These logical foundations help us build valid reasoning.