关于睡眠和清醒的，我们必须考虑它们是什么：他们是否特有的灵魂或机构，或双方共同;若共同的，以什么样的灵魂或身体的一部分，他们附言：进一步，从它产生的原因是什么他们是动物的属性，是否所有的动物在他们两个，或一些市场份额分享一个只，其他其他只，或一些分享和双方都不一些。此外，除了这些问题的，我们还必须询问的梦想是什么，从什么事业露宿者有时梦想，有时不，还是事实是，露宿者总是梦想，但并非都记得（梦想）和如果发生这种情况，它的解释是什么。同样，[我们必须询问]是否有可能或不预见未来（在梦中），如果有可能，以何种方式，进一步，是否可以假设，它仅适用于事情由完成的人，或那些机构还对其中的原因在于，人类机构，并从自然，或自发性的运作造成段。首先，然后，有一点是明确的，即属于每清醒和睡眠的相同部分动物，因为它们是对立的，和睡眠显然是一醒来困苦。对于对立物，自然以及在其他事情上，总是被视为存在于同一问题本身，成为同一感情：例子是健康和疾病，美丑，实力和弱点，视力和失明，听力和耳聋。这也是清楚以下考虑。该标准是我们知道醒人醒与该由我们知道卧铺睡着了相同的;
    ====
    WITH regard to sleep and waking, we must consider what they are: whether they are peculiar to soul or to body, or common to both; and if common, to what part of soul or body they appertain: further, from what cause it arises that they are attributes of animals, and whether all animals share in them both, or some partake of the one only, others of the other only, or some partake of neither and some of both. Further, in addition to these questions, we must also inquire what the dream is, and from what cause sleepers sometimes dream, and sometimes do not; or whether the truth is that sleepers always dream but do not always remember (their dream); and if this occurs, what its explanation is. Again, [we must inquire] whether it is possible or not to foresee the future (in dreams), and if it be possible, in what manner; further, whether, supposing it possible, it extends only to things to be accomplished by the agency of Man, or to those also of which the cause lies in supra-human agency, and which result from the workings of Nature, or of Spontaneity. First, then, this much is clear, that waking and sleep appertain to the same part of an animal, inasmuch as they are opposites, and sleep is evidently a privation of waking. For contraries, in natural as well as in all other matters, are seen always to present themselves in the same subject, and to be affections of the same: examples are-health and sickness, beauty and ugliness, strength and weakness, sight and blindness, hearing and deafness. This is also clear from the following considerations. The criterion by which we know the waking person to be awake is identical with that by which we know the sleeper to be asleep;