Argumentum ad hominem. An argument which, whatever it
be in itself, or however inoperative on others, is of constraining
effect on the person to whom it is addressed, either because based on
some principle for which he himself contends, or on the general maxims
which regulate his conduct. Butler's Analogy is such an argument, being
addressed to the Deist; and the Atheist or Pantheist might admit its
validity, but deny that it has any bearing on their positions.