To prove the power of the mind over the body, Mr Godwin
observes, "How often do we find a piece of good news dissipating a
distemper? How common is the remark that those accidents which
are to the indolent a source of disease are forgotten and
extirpated in the busy and active? I walk twenty miles in an
indolent and half determined temper and am extremely fatigued. I
walk twenty miles full of ardour, and with a motive that
engrosses my soul, and I come in as fresh and as alert as when I
began my journey. Emotion excited by some unexpected word, by a
letter that is delivered to us, occasions the most extraordinary
revolutions in our frame, accelerates the circulation, causes the
heart to palpitate, the tongue to refuse its office, and has been
known to occasion death by extreme anguish or extreme joy. There
is nothing indeed of which the physician is more aware than of
the power of the mind in assisting or reading convalescence."

The instances here mentioned are chiefly instances of the
effects of mental stimulants on the bodily frame. No person has
ever for a moment doubted the near, though mysterious, connection
of mind and body. But it is arguing totally without knowledge of
the nature of stimulants to suppose, either that they can be
applied continually with equal strength, or if they could be so
applied, for a time, that they would not exhaust and wear out the
subject. In some of the cases here noticed, the strength of the
stimulus depends upon its novelty and unexpectedness. Such a
stimulus cannot, from its nature, be repeated often with the same
effect, as it would by repetition lose that property which gives
it its strength.

In the other cases, the argument is from a small and partial