for aristotle the basic structure of an argument was

The Aristotelian or classical argument is a style of argument developed by the famous Greek philosopher and rhetorician, Aristotle. In this style of argument, your goal as a writer is to convince your audience of something. The goal is to use a series of strategies to persuade your audience to adopt your side of the issue. Although ethos, pathos, and logos play a role in any argument, this style of argument utilizes them in the most persuasive ways possible.

1. Introduce your issue. At the end of your introduction, most professors will ask you to present your thesis. The idea is to present your readers with your main point and then dig into it.
2. Present your case by explaining the issue in detail and why something must be done or a way of thinking is not working. This will take place over several paragraphs.
3. Address the opposition. Use a few paragraphs to explain the other side. Refute the opposition one point at a time.
4. Provide your proof. After you address the other side, you’ll want to provide clear evidence that your side is the best side.
5. Present your conclusion. In your conclusion, you should remind your readers of your main point or thesis and summarize the key points of your argument. If you are arguing for some kind of change, this is a good place to give your audience a call to action. Tell them what they could do to make a change.

The ancient commentators grouped together several of Aristotle’s treatises under the title Organon (“Instrument”) and regarded them as comprising his logical works:
One major difference between Aristotle’s understanding of predication and modern (i.e., post-Fregean) logic is that Aristotle treats individual predications and general predications as similar in logical form: he gives the same analysis to “Socrates is an animal” and “Humans are animals”. However, he notes that when the subject is a universal, predication takes on two forms: it can be either universal or particular. These expressions are parallel to those with which Aristotle distinguishes universal and particular terms, and Aristotle is aware of that, explicitly distinguishing between a term being a universal and a term being universally predicated of another.

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Rogerian argument, or consensus-building argument, aims to develop commonality among readers rather than establish an adversarial relationship.

Plato had posed the question of whether the best life consists in the pursuit of pleasure or the exercise of the intellectual virtues. Aristotle’s answer is that, properly understood, the two are not in competition with each other. The exercise of the highest form of virtue is the very same thing as the truest form of pleasure; each is identical with the other and with happiness. The highest virtues are the intellectual ones, and among them Aristotle distinguished between wisdom and understanding. To the question of whether happiness is to be identified with the pleasure of wisdom or with the pleasure of understanding, Aristotle gives different answers in his main ethical treatises. In the Nicomachean Ethics perfect happiness, though it presupposes the moral virtues, is constituted solely by the activity of philosophical contemplation, whereas in the Eudemian Ethics it consists in the harmonious exercise of all the virtues, intellectual and moral.
Aristotle’s theoretical concept of soul differs from that of Plato before him and René Descartes (1596–1650) after him. A soul, for him, is not an interior immaterial agent acting on a body. Soul and body are no more distinct from each other than the impress of a seal is distinct from the wax on which it is impressed. The parts of the soul, moreover, are faculties, which are distinguished from each other by their operations and their objects. The power of growth is distinct from the power of sensation because growing and feeling are two different activities, and the sense of sight differs from the sense of hearing not because eyes are different from ears but because colours are different from sounds.

We should point out that Aristotle does not restrict himself to a consideration of purely formal issues in his discussion of rhetoric. He famously distinguishes, for example, between three means of persuasion: ethos, pathos, and logos. As we read, at the beginning of his Rhetoric: “Of the modes of persuasion furnished by the spoken word there are three kinds. . . . [Firstly,] persuasion is achieved by the speaker’s personal character when the speech is so spoken as to make us think him credible. . . . Secondly, persuasion may come through the hearers, when the speech stirs their emotions. . . . Thirdly, persuasion is effected through the speech itself when we have proved [the point] by means of the persuasive arguments suitable to the case in question.” (Rhetoric, I.2.1356a2-21, Roberts.) Aristotle concludes that effective arguers must (1) understand morality and be able to convince an audience that they themselves are good, trustworthy people worth listening to (ethos); (2) know the general causes of emotion and be able to elicit them from specific audience (pathos); and (3) be able to use logical techniques to make convincing (not necessarily sound) arguments (logos). Aristotle broaches many other issues we cannot enter into here. He acknowledges that the goal of rhetoric is persuasion, not truth. Such techniques may be bent to immoral or dishonest ends. Nonetheless, he insists that it is in the public interest to provide a comprehensive and systematic survey of the field.
Aristotle examines the way in which these four different categorical propositions are related to one another. His views have come down to us as “the square of opposition,” a mnemonic diagram that captures, systematizes, and slightly extends what Aristotle says in De Interpretatione. (Cf. 6.17a25ff.)

References:

http://plato.stanford.edu/entries/aristotle-logic/
http://www.umgc.edu/current-students/learning-resources/writing-center/online-guide-to-writing/tutorial/chapter8/ch8-03.html
http://www.britannica.com/biography/Aristotle/Philosophy-of-mind
http://www.iep.utm.edu/aris-log/
http://slideplayer.com/slide/6283880/