The Principle Principle

One of my correspondents likes to refer to what he calls the "harm principle." I think it offends him that some of us find this so-called principle incoherent and unintelligible. What is a principle? Are there criteria something ought to meet so that it can be called a principle and not a slogan?

I always like to start with the dictionary. What is a principle? According to The American Heritage Dictionary, Third Edition (Office Edition) (1994), a principle is:

n. 1. A basic truth, law, or assumption. 2.a.A rule or standard, esp. of good behavior. b. Moral or ethical standards or judgments. 3. A fixed or predetermined policy. 4. A rule or law concerning the functioning of natural phenomena or mechanical processes. 5. A basic source. Page 658.

Webster's College Dictionary (2003) gives us this:

n 1 a: a fundamental law or doctrine b: a rule or code of conduct c: devotion to right principles d: the laws or facts of nature underlying the working of an artificial device (trying to grasp the principles of radar) 2 a: a primary source : ORIGIN b: an underlying faculty or endowment (such principles of human nature as greed and curiosity) 3: a constituent that exhibits or imparts a characteristic quality (quinine is the active principle of cinchona bark)

The New Roget's Thesaurus in Dictionary Form, Revised Edition (1976), at page 324, has the following entry:

principle, n. regulation, law prescript (RULE)

All of which goes to this point: A principle is similar to what Kant called a maxim, a rule of behavior, a guide to practice. We are, thus, in the realm of practical reason, and we would expect to find guidance. The form of a statement of such a principle should be along the lines of "One should always act in such a way as to ...," or "One should never act so as to ...," and so on.

An example of a principle might be: "Do unto others as you would have others do unto you."

A principle, looked at another way, is a statement which could serve as the major premise of a practical syllogism.