me of a number of cases, which had been brought on by
drinking porter, and other stimulant liquors, without knowing the
taste of water. In many of these cases if a moderate quantity of
water were drank every day they would be cured; but you would find
few who would follow such plain and simple directions. How then must
a physician proceed? Why, as is generally done by the most judicious:
they direct their patients to Bath or Buxton, and there advise them
to swallow a certain quantity of water every day, which they do most
scrupulously, and, of course, return home cured.

As causes of asthenic disease, we must not omit the undue exercise of
the intellectual functions. Thinking is a powerful exciting cause,
and produces effects similar to those of intoxication. None of the
exciting powers have more influence upon our activity, than the
exercise of the intellectual powers, as well as passion and emotion.
Homer, the great observer and copyist of nature, observes of the
hero, whom he gives for a pattern of eloquence, that, upon his first
address, before he had got into his train of thought, he was awkward
in every motion, and in his whole attitude; he looked down upon the
ground, and his hands hung straight along his sides, as if they had
lost the power of motion; and his whole appearance was a picture of
torpidity. But when he had once fairly entered upon his subject, his
eyes were all on fire, his limbs all motion, grace, and energy.

Hence, as the exercise of the intellectual functions evidently
stimulates, an excess of thinking must bring on indirect debility, by
exhausting the excitability. But though we do meet with instances of
indirect debility arising from this source, it must be confessed that
they much oftener arise from the use of very different stimulants.

As excessive exercise of the intellectual powers will bring on
indirect debility, so the deficient, weak, or vacant state of mind,
which is unable to carry on a train of thinking, will produce direct
debility. Indeed this debility often occurs to those whose minds have
been all their life actively engaged in business, but who have at
last retired to enjoy themselves, without having a cultivated mind
fit for retirement. They become languid, inert, and low spirited, for
want of the stimulus of mental exertion; and in many cases cannot be
completely restored to health, till they are again engaged in their
usual occupations.

Violent passions of the mind, su