It's been a bit since I took formal logic, so this is just a question of technicality and I can't find a thread that deals with it already (though it seems like one should be here somewhere...Seems impossible that it's never been brought up. I assume I'm not searching well enough, but I'm also short on time :p )

I'm in a discussion and definitions have been introduced (oh sweet danger, how I love you!). Here is the quote from the other person:

"I didn't make up the notion of "irrational argument", it is an accepted philosophical term that I picked up in Philosophy. Anytime two or more sides can not PROVE their assumption, yet continue to argue it, it is called an irrational argument."

Now...when I think argument, I think formal logic, which I don't necessarily think is what he is thinking here (but might be - I had been assuming he'd been using "irrational" in a more layman's term variety than it appears he thinks he is, so anything is possible).

But I can't find anything that directly addresses an accepted philosophical definition of "irrational argument" though I know there has to be one. I know are are valid, invalid, sound, and unsound arguments...but I'm not seeing "irrational" or "rational"...and I do seem to recall the idea was very very briefly discussed in my basic logic class and that those terms were more or less set aside because they don't really mean anything in formal logic (but I could be quite wrong!). Guidance? Thoughts?

Thanks!

How do you know that there "has to be" an accepted philosophical definition of "irrational argument"?

It is always possible that the person took a philosophy class and his teacher used the phrase in that way, which, frankly, seems similar to common use (though if there is more to it that you are leaving out, then it may not be). But as far as I know, it is a phrase that does not have any technical meaning to logicians, unlike words like "valid" and "sound".

My advice is to go ahead and let him use the phrase as he says in that thread, and to adopt his use, in that thread, assuming that there is not more to it than just what you stated, that is not obvious. If there are people who are having a disagreement, and they present arguments with premises that the other person does not accept, it is fairly pointless to simply repeat the argument. One would need to develop an argument for whatever premises are in dispute (assuming, of course, that we are dealing with valid deductive arguments or good inductive ones), or simply come up with a new argument, or abandon one's position, or simply end the discussion.

Anytime two or more sides can not PROVE their assumption, yet continue to argue it, it is called an irrational argument."

Suppose I say, "All men are mortal and Sokrates was a man and therefore Sokrates is mortal." Now this is a correct argument from a logical standpoint. Some moron refuses to accept the conclusion, citing all sorts of completely non-relevant points, or simply refuses to accept logic as somehow binding as a "proof." If both are stubborn, there will never be agreement about our Sokrates, but in this case is my syllogism irrational?

No, it is "rational". But take the hypothetical syllogism, 1. All men are mortal. 2. Socrates is mortal. Therefore, 3. Socrates is a man. That syllogism is invalid, and if an invalid syllogism is irrational, it is irrational. Perhaps a better case would be to argue that President Obama is a Communist, because he is in favor of universal health care, and all Communists are in favor of universal health care. That commits the fallacy of the undistributed middle term.

Is there any particular reason you spell "Socrates" that way?

Famous old people usually have different names in different languages. In danish it is Sokrates, Aristoteles, Platon. It is Socrates, Aristotle, Plato in english. I don't know why. Accoridng to Wiki, the original spelling used a K.

I wondered why he spelled it with a 'K' when he was writing English.

Maybe he isn't a native English speaker, and prefers what he is accustomed to seeing (or wrote it that way out of habit). Of course, since we are discussing an individual's motivation for a particular action, it might be best to let him speak for himself.

Right. But I think he is Australian.

Maybe he reads Plato in the original Greek. Besides, Australians don't speak English.

From an orthographical, phonetical, and etymological viewpoint, the transliteration of the Greek kappa to the English K seems preferable to retaining the Roman one of using their hard C. Hence, some English linguists opt to reverse the Latin transliteration process for Greek proper names.

Famous old people usually have different names in different languages. In danish it is Sokrates, Aristoteles, Platon. It is Socrates, Aristotle, Plato in english. I don't know why. Accoridng to Wiki, the original spelling used a K.