Authors:

[I]n principle and in practice, in a right track and in a wrong one, the rarest of all human qualities is consistency.

Jeremy Bentham (1838). “The works of Jeremy Bentham, now first collected: under the superintendence of his executor, John Bowring ...”, p.2
[I]n principle and in practice, in a right track and in a wrong one, the rarest of all human qualities is consistency.