Let these be the matters stated concerning the differences both of the number and some (of the means?) of imitation.
4. Some two causes, and these natural ones, seem to have given birth to poetics.
For both imitating is natural  to men from childhood--they differ from the other animals in that [man] is the greatest imitator and he crafts his first acquisitions of knowledge  through imitation--and also all men delight in imitations.
And the proof of this is what happens in the event: for we enjoy seeing especially accurate likenesses of things which we observe with discomfort, for example the transformations of the most dishonourable beasts and corpses. And the cause is this: because to learn is supremely enjoyable not only for lovers of wisdom but is so for others in the same way though they share in this for a short time. For because of this those who view the images enjoy them, because it happens that those who observe learn and conclude what each [is]—i.e., this is that. When someone happens not to have previously seen [the object], the imitation does not indeed craft the enjoyment but [it is] through the workmanship or the color  or some other such cause.
And since there is in us, according to nature, the imitation of both harmony and rhythm (for it is clear that meters are parts of rhythms) men developed from the beginning [stage], specifically in respect to these things, and progressing little by little, they produced the poetic work from their experimentations; for the more distinguished [poets] imitated excellent deeds and the deeds of those sorts of men, while those of a poorer rate the deeds of petty men  at first crafting censorious works, just as the others [crafted] praises and encomia.
While we can mention this sort of poetic work of not one of those prior to Homer, though it is likely there were many, after Homer (for example his Margites and other such sorts of poetical works) there are those beginning with whom the connected iambic meter came—on account of which it is now called “iambic”, because in this meter they “iambicized” (lampooned) each other. Some of the ancients also originated heroic meters and some iambics; and just as Homer was ‘the poet’ in respect to the most weighty matters (because he crafted well but also because he crafted dramatic imitations) so thus he was also the first one who displayed the dramatic poetic forms of comedy, not satirically but humorously; for the Margites has an analogy: as the Iliad and the Odyssey are to tragedies, so is this work to comedies.
 “poetics” for the abstract noun “poetikh” as that seems to be general enough to insinuate more than English poesy.
 the adjective is a compound (literally “with nature”) that also means, “innate, inborn, inbred.”
 Yes this is awkward -- here again I could be accused of overtranslation as “acquisitions of knowledge” is simply one word that is often translated simply as “education” or “lessons” and who “crafts an acquisition”? However, the verb is in the middle voice and I wanted to get across the idea that men ‘make the lessons’ for (or ‘teach’) themselves; simply saying ‘educate’ or ‘learn’ here implies for us a classroom, pedagogical setting, whereas Aristotle is speaking of the nature of man: on his own he is an ‘imitator’ from the first, this is how he learns, and he does it by that same crafting (poiew—the verb that this whole treatise is on) that he uses to make poetical works.
 The point is clear, but I really don’t know what this means. Does he mean snake molting and the rotting of corpses?
 “superficial appearance”
 could also be “impromptus” which resonates with the mention of “rhythm” and “harmony” above, but that English word is understood too exclusively musically, for Ar. clearly understands poetry in general (playwriting verse, etc.) as well as instrument-craft.
 here the contrast in the deeds is phaulos and kalos instead of phaulos with spoudaios as above (1448a, section 2, see Burglar’s note #1). If there are objections an aristocratic tone I refer the reader to the Politics.