world as it is.  It was used against Kant by his opponents, who thought in this way to refute his teachings.[3] The Sceptics could not, of course, accept a theory of nature that included the soul and the external world in one harmonious whole, but Sextus in his discussion of the third Trope does not refute this argument as fully as he does later in his work against logic.[4] He simply states here that philosophers themselves cannot agree as to what nature is, and furthermore, that a philosopher himself is a part of the discord, and to be judged, rather than being capable of judging, and that no conclusion can be reached by those who are themselves an element of the uncertainty.[5]

    [1] Hyp. I. 96-97.

    [2] Adv.  Math. VII. 93.

    [3] Ueberweg Op. cit. 195.

    [4] Adv.  Math. VII. 354.

    [5] Hyp. I. 98-99.

The Fourth Trope.  This Trope limits the argument to each separate sense, and the effect is considered of the condition of body and mind upon sense-perception in relation to the several sense-organs.[1] The physical states which modify sense-perception are health and illness, sleeping and waking, youth and age, hunger and satiety, drunkenness and sobriety.  All of these conditions of the body entirely change the character of the mental images, producing different judgments of the color, taste, and temperature of objects, and of the character of sounds.  A man who is asleep is in a different world from one awake, the existence of both worlds being relative to the condition of waking and sleeping.[2]

The subjective states which Sextus mentions here as modifying the character of the mental representations are hating or loving, courage or fear, sorrow or joy, and sanity or insanity.[3] No man is ever twice in exactly the same condition of body or mind, and never able to review the differences of his ideas as a sum total, for those of the present moment only are subject to careful inspection.[4] Furthermore, no one is free from the influence of all conditions of body or mind, so that he can be unbiassed to judge his ideas, and no criterion can be established that can be shown to be true, but on the contrary, whatever course is pursued on the subject, both the criterion and the proof will be thrown into the circulus in probando, for the truth of each rests on the other.[5]

    [1] Hyp. I. 100.

    [2] Hyp. I. 104.

    [3] Hyp. I. 100.

    [4] Hyp. I. 112.

    [5] Hyp. I. 117.