perform!

ESSAY VIII. OF HUMAN VEGETATION.

There is another point of view from which we may look at the subject of
time as it is concerned with the business of human life, that will lead
us to conclusions of a very different sort from those which are set down
in the preceding Essay.

Man has two states of existence in a striking degree distinguished from
each other: the state in which he is found during his waking hours; and
the state in which he is during sleep.

The question has been agitated by Locke and other philosophers, "whether
the soul always thinks," in other words, whether the mind, during those
hours in which our limbs lie for the most part in a state of
inactivity, is or is not engaged by a perpetual succession of images and
impressions. This is a point that can perhaps never be settled. When the
empire of sleep ceases, or when we are roused from sleep, we are often
conscious that we have been to that moment busily employed with that
sort of conceptions and scenes which we call dreams. And at times when,
on waking, we have no such consciousness, we can never perhaps be sure
that the shock that waked us, had not the effect of driving away these
fugitive and unsubstantial images. There are men who are accustomed to
say, they never dream. If in reality the mind of man, from the hour of
his birth, must by the law of its nature be constantly occupied with
sensations or images (and of the contrary we can never be sure), then
these men are all their lives in the state of persons, upon whom the
shock that wakes them, has the effect of driving away such fugitive
and unsubstantial images.--Add to which, there may be sensations in
the human subject, of a species confused and unpronounced, which never
arrive at that degree of distinctness as to take the shape of what we
call dreaming.

So much for man in the state of sleep.

But during our waking hours, our minds are very differently occupied at
different periods of the day. I would particularly distinguish the two
dissimilar states of the waking man, when the mind is indolent, and when
it is on the alert.

While I am writing this Essay, my mind may be said to be on the alert.
It is on the alert, so long as I am attentively reading a book of
philosophy, of argumentation, of eloquence, or of poetry.

It is on the alert, so long as I am addressing a smaller or a greater
audience, and endeavouring either to amuse or instruct them. It is on
the alert, whil