De somno et vigilia theses ad disputandum propositae

or the performance of other business, as well as with snoring, grinding of teeth, and if there are other things of this kind: another occurs without these.

LI.

As for the position of the body: one sleep is captured while sitting, another while lying down, with the head high or low, the body supine or prone, or reclining on the right or left side. As for the place: it occurs either in a warm place or a cold one, etc., in a bed either soft or hard. Finally, by reason of time, it is either nocturnal or diurnal; and this is either morning, midday, or evening.

LII.

What we have said so far regarding the differences of sleep seems meager at first glance; yet they are of greater moment for investigating the effects of sleep and waking.

LIII.

Moreover, since no action can occur without the ministry of calidum innatum innate heat, it is necessary for it to be moved outward during vigils so that external functions may be performed. During sleep, however, while the outermost parts rest from their actions and have less need of the innate heat, it is consonant with reason that this same heat be received inward (unless something prevents it) and be detained there to carry out internal duties. Hence it comes about that the effects of heat are ascribed to it when it is clinging within during sleep, and to it when it is moving externally during vigils.

LIV.

But the variety of these is manifold; which is partly attributed to the nature of sleep, and partly happens by accident, because, namely, more conditions supervene upon the contraction of heat, according to the diversity of sleep and the body or matter into which it acts.

LV.

A just comparison of these three will define the effects of any sleep and