In Ancient Greece, there lived a talkative and thoughtful fellow who was socially awkward enough that he failed to respect conversational boundaries, yet smart enough that he knew how to call people out on their foolishness. This is, of course, Socrates, who didn’t claim to be so smart. He asked folks about presumably basic topics like "courage" and "self-control", claiming that he didn't really understand them.
Socrates asked apparent experts to walk him through the details so that he could come to understand them, at least a bit. As Plato tells it, these initially light conversations go from bad to worse as the experts can't manage to give Socrates a solid case for their own perspectives on these topics. In fact, they're routinely forced to admit that they don't really know what they're talking about.
More than an ancient tale of intellectual one-upmanship, this is among history's most iconic demonstrations of logic in action. In a logical nutshell:
Attempting to define words & sentences meaningfully and precisely
Structuring sentences into an argument
Checking to make sure that the argument and those meanings produce a coherent line of reasoning that has a shot at drawing a true conclusion
Like other figures in other ancient societies - some notable Indian and Chinese come to mind - Socrates shows us that we can be thoughtful and precise in a way that allows us to build a solid argument and come to a specific conclusion. There's a catch. The cost is that, because our thoughts are explicit and not vague, our argument can be corrected just as precisely. We can be shown where we're wrong. So, we must adjust and build a better argument.
On the other hand, our thoughts can remain vague, and we can remain free of any need to argue our point. Then we have no reason to think we're right, so it's shallow of us to hold that a certain precise conclusion is true. This was the mistake of the friends Socrates chatted with: they assumed they had something figured out but had never really thought about it logically.
Aristotle put this way of thinking under his scrutiny. As best he could see, he could reduce logical thinking to a basic set of structures. The basic structure of an argument was, for Aristotle, syllogism. It runs something like this: "If A is B, and if B is C, then A is C".
You can fill in A, B, and C with your own favorite terms to see what he was getting at. Here's my preference: "If little Russian nesting doll fits inside medium Russian nesting doll and medium Russian nesting doll fits inside big Russian nesting doll, then little Russian nesting doll fits inside big Russian nesting doll". Or try this popular syllogism: "All men are mortal, Socrates is a man, so Socrates is mortal". It may seem basic, but in all syllogisms, we can use two supporting pieces of information to draw a novel conclusion that's not in that information. This conclusion gets called an inference.
Okay, we've used Socrates to look at logic to tighten our understanding of a topic (the contents of our reasoning). We've used Aristotle to view logic as a way of structuring thoughts regardless of their contents (the form of our reasoning).
That second part of logic, called formal logic, has done a lot to shape the makeup of logic over the centuries. Logicians have contributed to developments in mathematics, computer science, and many other endeavors by thinking abstractly with variables and operators to connect them.
Rewind to that syllogism stuff. Logically, any syllogism with this structure (A is B, B is C, so A is C) is considered valid. That should mean it always works, right? Not so fast... We can fill that formula in with some strange stuff. The conclusion doesn't have to be true for us to call this structure logical. Valid logic gives us true conclusions if we have true information, to begin with. Verifying the accuracy of your content means doing your homework on whatever it is you're arguing about.
There are so many disciplines that study specific topics rigorously and in detail. Meteorologists aren't stuck imagining the reasonable possible conclusions they can come to about the weather. They can use logic to come to specific conclusions backed by their observations. Historians don't just think about logically possible sequences of events in the past. They argue for specific chronologies based on their studies. It's still logic, it's still logical, but the content is as specialized as the tools and methods used by experts in these fields. (Nativlang.com)
Rhetoric first came into fashion during the classical societies of Ancient Greece and Rome. As governance evolved into first democratic and then republican ideals, those who could persuade, convince and communicate ideas became the leaders and those looked up to. A leader, skilled in the art of Rhetoric could literally rule the city, the country, or the world. Good rhetorical skills deliver a strong MESSAGE to an AUDIENCE that the SPEAKER understands and is seen as credible.
The appeal of the MESSAGE should address the audiences ETHOS (ethical appeal based on character, credibility, and reliability of the SPEAKER), LOGOS (logical appeal to truths, logic, and reason of the audience), and PATHOS (an appeal to emotion and the audiences needs and values).
Saint Augustine of Hippo (354–430)
Francesco Petrarch (1304–1374)