wiktionary:principle

A principle is something, usually a rule or norm, that is part of the basis for something else. For example, the ethics of someone may be seen as a set of principles that the individual obeys. These principles form the basis for their ethics. Principles may also be introduced as pedagogy: laying down basics in a topic, in order later to proceed to more detailed developments. Identifying or defining a rule as a principle says that, for the purpose at hand, the principle will not be questioned or further derived. This is a convenient way ...

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