_e._ The fifth treatise, finally, deals with the Sophistical Elenchi (σοφιστικοὶ ἔλεγχοι), or ‘On Refutations,’ as in the unconscious escape of thought in its categories to the material side of popular conception, it arrives at constant contradiction with itself. The sophistical elenchi betray the unconscious ordinary idea into these contradictions, and make it conscious of them, in order to entrap and puzzle it; they were mentioned by us in connection with Zeno, and the Sophists sought them out, but it was the Megarics who were specially strong in them. Aristotle goes through a number of such contradictions by the way of solving them; in so doing he proceeds quietly and carefully, and spares no pains, though they might have been made more dramatic. We have before (Vol. I. pp. 456-459) found specimens of these in treating of the Megarics, and we have seen how Aristotle solves such contradictions through distinction and determination. Of these five parts of the Aristotelian Organon, what is produced in our ordinary systems of logic is, as a matter of fact, of the slightest and most trivial description, consisting as it does mainly of what is contained in the introduction of Porphyry. More particularly in the first parts, in the Interpretation and in the Analytics, this Aristotelian logic contains these representations of universal forms of thought, such as are now dealt with in ordinary logic, and really form the basis of what in modern times is known as logic. Aristotle has rendered a never-ending service in having recognized and determined the forms which thought assumes within us. For what interests us is the concrete thought immersed as it is in externalities; these forms constitute a net of eternal activity sunk within it, and the operation of setting in their places those fine threads which are drawn throughout everything, is a masterpiece of empiricism, and this knowledge is absolutely valuable. Even contemplation, or a knowledge of the numerous forms and modes assumed by this activity, is interesting and important enough. For however dry and contentless the enumeration of the different kinds of judgments and conclusions, and their numerous limitations may appear to us to be, and though they may not seem to serve their purpose of discovering the truth, at least no other science in opposition to this one can be elevated into its place. For instance, if it is held to be a worthy endeavour to gain a knowledge of the infinite number of animals, such as one hundred and sixty-seven kinds of cuckoo, in which one may have the tuft on his head differently shaped from another, or to make acquaintance with some miserable new species of a miserable kind of moss which is no better than a scab, or with an insect, vermin, bug, &c., in some learned work on entomology, it is much more important to be acquainted with the manifold kinds of movement present in thought, than to know about such creatures. The