e
agunt vigilantes, agitantque, ea cuique in somno accidunt. _De Div._

[85] Essay on Human Understanding, book, chap. i. sect 17.

[86] Obs, on Man, vol. 1, sect. 5.

[87] There is a phenomenon in the mind, which, though it happen to us
while we are perfectly awake, yet approaches the nearest to sleep of any
I know. It is called the _Reverie_, or, as some term it, the _brown
study_, a sort of middle state between waking and sleeping; in which,
though our eyes are open, our senses seem to be entirely shut up, and we
are quite insensible of every thing about us, yet we are all the while
engaged in a musing indolence of thought, or a supine and lolling kind
of roving from one fairy scene to another, without any self-command;
from which, if any noise or accident rouse us, we wake as from a real
dream, and are often as much at a loss to tell how our thoughts were
employed, as if we had waked from the soundest sleep. This is frequently
called _dreaming_, sometimes _absence_, a thing often observed in lovers
and people of a melancholy or indeed speculative turn.--_Fordyce's
Dialogues concerning education, vol. II. p. 255._

[88] Leviathan, part. 1. c. 1.

CHAPTER XI.

ON INCUBATION; OR THE ART OF HEALING BY VISIONARY DIVINATION.

Medicine unquestionably ranks among the most ancient of all human
sciences. In the infant state of society, when simplicity of manners
characterised the pursuits of mankind, medical assistance was little
wanted; but when the nature of man degenerated, and vice and luxury
corrupted his habits of innocence and temperance, diseases sprung up
which those aids alone could check or eradicate. The knowledge of them
at first could not fail to be empirical and precarious. The sick were
placed in the high ways, that travellers and passers by might assist
them with their counsel; and at length the priesthood appropriated this
privilege exclusively to themselves.

It was not merely the sacerdotal dignity which rendered them objects of
awe and reverence to the illiterate multitude; the priests were regarded
as the depositaries of science and learning; and proved themselves as
skilful as they were successful, in cementing their influence by those
arts which were best calculated to inflame the prejudices of the vulgar
in their favour.

It is the work of ages to wean men and nations from popular illusions,
and the deep-rooted opinions transmitted from sire to son: it cannot
therefore surprise us,