principleyoudaoicibaDictYouDict[principle 词源字典]
principle: [14] Frequently confused, principal [13] and principle come from distinct sources – but both sources were derived ultimately from Latin princeps ‘chief’ (from which English gets prince). Principal goes back via Old French principal to Latin principālis ‘first, original’, while principle comes from *principle, an assumed Anglo-Norman variant of Old French principle, which went back to Latin principium ‘beginning, foundation’.
=> first, prime, prince[principle etymology, principle origin, 英语词源]
principle (n.)youdaoicibaDictYouDict
late 14c., "origin, source, beginning; rule of conduct; axiom, basic assumption; elemental aspect of a craft or discipline," from Anglo-French principle, Old French principe "origin, cause, principle," from Latin principium (plural principia) "a beginning, commencement, origin, first part," in plural "foundation, elements," from princeps (see prince). Used absolutely for (good or moral) principle from 1650s.
It is often easier to fight for principles than to live up to them. [Adlai Stevenson, speech, New York City, Aug. 27, 1952]
Scientific sense of "general law of nature" is recorded from 1802. The English -l- apparently is by analogy of participle, etc.