Discovery in general has been explained already. As for the species of Discovery, the first to be noted is (1) the least artistic form of it, of which the poets make most use through mere lack of invention, Discovery by signs or marks. Of these signs some are congenital, like the ‘lance-head which the Earth-born have on them’, or ‘stars’, such as Carcinus brings in in his Thyestes; others acquired after birth—these latter being either marks on the body, e.g. scars, or external tokens, like necklaces, or to take another sort of instance, the ark in the Discovery in Tyro. Even these, however, admit of two uses, a better and a worse; the scar of Ulysses is an instance; the Discovery of him through it is made in one way by the nurse and in another by the swineherds. A Discovery using signs as a means of assurance is less artistic, as indeed are all such as imply reflection; whereas one bringing them in all of a sudden, as in the Bath-story, is of a better order. Next after these are (2) Discoveries made directly by the poet; which are inartistic for that very reason; e.g. Orestes’ Discovery of himself in Iphigenia: whereas his sister reveals who she is by the letter, Orestes is made to say himself what the poet rather than the story demands. This, therefore, is not far removed from the first-mentioned fault, since he might have presented certain tokens as well. Another instance is the ‘shuttle’s voice’ in the Tereus of Sophocles. (3) A third species is Discovery through memory, from a man’s consciousness being awakened by something seen or heard. Thus in The Cyprioe of Dicaeogenes, the sight of the picture makes the man burst into tears; and in the Tale of Alcinous, hearing the harper Ulysses is reminded of the past and weeps; the Discovery of them being the result. (4) A fourth kind is Discovery through reasoning; e.g. in The Choephoroe: ‘One like me is here; there is no one like me but Orestes; he, therefore, must be here.’ Or that which Polyidus the Sophist suggested for Iphigenia; since it was natural for Orestes to reflect: ‘My sister was sacrificed, and I am to be sacrificed like her.’ Or that in the Tydeus of Theodectes: ‘I came to find a son, and am to die myself.’ Or that in The Phinidae: on seeing the place the women inferred their fate, that they were to die there, since they had also been exposed there. (5) There is, too, a composite Discovery arising from bad reasoning on the side of the other party. An instance of it is in Ulysses the False Messenger: he said he should know the bow—which he had not seen; but to suppose from that that he would know it again (as though he had once seen it) was bad reasoning. (6) The best of all Discoveries, however, is that arising from the incidents themselves, when the great surprise comes about through a probable incident, like that in the Oedipus of Sophocles; and also in Iphigenia; for it was not improbable that she should wish to have a letter taken home. These last are the only Discoveries independent of the artifice of signs and necklaces. Next after them come Discoveries through reasoning.