Credulity has been justly defined, _Belief without Reason_. Scepticism
is its opposite, _Reason without Belief_ and is the natural and
invariable consequence of credulity: for it may be generally observed,
that men who believe without reason, are succeeded by others whom no
reasoning can convince; a fact which has occasioned many extraordinary
and violent revolutions in the _Materia Medica_, and a knowledge of it
will enable us to explain the otherwise unaccountable rise and fall of
many useless, as well as important articles. It will also suggest to the
reflecting practitioner, a caution of great moment, to avoid the
dangerous fault imputed to Galen by Dioscorides, of ascribing too many
and too great virtues to one and the same medicine. _By bestowing
unworthy and extravagant praise upon a remedy, we in reality do but
detract from its reputation,[36] and run the risk of banishing it from
practice_; for when the sober practitioner discovers by experience that
a medicine falls so far short of the efficacy ascribed to it, he
abandons its use in disgust, and is even unwilling to concede to it that
degree of merit to which in truth and justice it may be entitled; the
inflated eulogiums bestowed upon the operation of _Digitalis_ in
pulmonary diseases, excited, for a time, a very unfair impression
against its use; and the injudicious manner in which the antisyphilitic
powers of _Nitric Acid_ have been aggrandised, had very nearly exploded
a valuable auxiliary from modern practice.
It is well known with what avidity the public embraced the expectations
given by Stöerk of Vienna in 1760, with respect to the efficacy of
_Hemlock_; every body, says Dr. Fothergill, made the extract, and every
body prescribed it, but finding that it would not perform the wonders
ascribed to it, and that a multitude of discordant diseases refused to
yield, as it was asserted they would, to its narcotic powers,
practitioners fell into the opposite extreme of absurdity, and declaring
that it could do nothing at all, dismissed it at once as inert and
useless. Can we not then predict the fate of the _Cubebs_, which has
been lately restored to notice with such extravagant praise and
unqualified approbation? May the sanguine advocates for the virtues of
the Colchicum derive a useful lesson of practical caution from these
precepts: it would be a matter of regret that a remedy which, under
skilful management, certainly possesses considerable virtue, should
again fall into obscurity and neglect from the disgust excited by the
extravagant zeal of its supporters.
There are, moreover, those who cherish a spirit of scepticism, from an
idea that it denotes the exercise of a superior intellect; it must be
admitted, that at that period in the history of Europe, when reason
first began to throw off the yoke of authority, it required superiority
of understanding as well as intrepidity of conduct, to resist the powers
of that superstition which had so long held it in captivity; but in the
present age, observes Mr. Dugald Stewart, “_unlimited scepticism is as
much the child of imbecility as implicit credulity_.” “He who at the end
of the eighteenth century,” says Rousseau, “has brought himself to
abandon all his early principles, without discrimination, would probably
have been a bigot in the days of the league.”