Elements of the philosophy of the human mind. By Dugald Stewart. Rev. and abridged, with critical and explanatory notes, for the use of colleges and schools. By Francis Bowen ...

DREAMING. 189
three questions, the f/ist belongs to the philosophy of the human
mind; and it is to this question that the following inquiry is
almost entirely confined. The second is more particularly interesting to the medical inquirer, and does not properly fall
under the plan of this work. The third seems to me to relate
to a subject, which is placed beyond the reach of the human
faculties.
It may be granted, that, if we could ascertain the state of the
mind in sleep, so as to be able to resolve the various phenomena
of dreaming into a smaller number of general principles; and
still more, if we could resolve them into one general fact, we
should be advanced a very important step in our inquiries upon
this subject; even although we should find it impossible to show,
in what manner this change in the state of the mind results from
the change which sleep produces in the state of the body. Such
a step would at least gratify, to a certain extent, that disposition
of our nature which prompts us to ascend from particular facts
to general laws, and which is the foundation of all our philosophical researches; and, in the present instance, I am inclined to
think, that it carries us as far as our imperfect faculties enable
us to proceed.
What circumstances accelerate or retard the approach of sleep. --
In conducting this inquiry with respect to the state of the mind
in sleep, it seems reasonable to expect, that some light may be
obtained from an examination of the circumstances which accelerate or retard its approach; for when we are disposed to rest,
it is natural to imagine, that the state of the mind approaches
to its state in sleep more nearly, than when we feel ourselves
alive and active, and capable of applying all our various faculties to their proper purposes.
In general, it may be remarked, that the approach of sleep is
accelerated by every circumstance which diminishes or suspends
the exercise of the mental powers; and is retarded by every
thing which has a contrary tendency. WVhen we wish for sleep,
we naturally endeavor to withhold, as much as possible, all the
active exertions of the mind, by disengaging our attention from
every interesting subject of thought. When we are disposed to