
Variant:
The existence of law is one thing; its merit or demerit is another. Whether it be or be not is one enquiry; whether it be or be not conformable to an assumed standard, is a different enquiry. A law, which actually exists, is a law, though we happen to dislike it, or though it vary from the text, by which we regulate our approbation and disapprobation.
John Austin, Austin Lectures on Jurisprudence; or The Philosophy of Positive Law, 1873, Lecture V
Source: The Province of Jurisprudence Determined (1832), p. 278