What is a source, or origin; that from which anything proceeds; fundamental substance or energy; primordial substance; ultimate element, or cause. The soul of man is an active principle. Tillotson called?

principle — A source, or origin; that from which anything proceeds; fundamental substance or energy; primordial substance; ultimate element, or cause. The soul of man is an active principle. Tillotson. (Webster's 1913.)

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