Posted: Jun 04, 2011 2:44 pm
Cito di Pense wrote:Sweenith wrote:
All I mean by "necessary" is this: a proposition or statement is necessary if and only if it's impossible for it to be false (like "2+2=4" or "All squares have four sides"). On the other hand, there are certain facts that could have been otherwise than they are, such as the fact that I live in Chicago, or the fact that my computer monitor is to the left of my can of diet Dr. Pepper—the universe might have been organized in such a way that I ended up in Japan, say, or that my monitor was to the right of the can instead of the left—these facts are not necessary, because it was possible for them not to be the case.
You're now behaving as if this conversation has never taken place before, let alone hundreds of times in this forum alone. What is your point? To observe that people have tried to define the words 'necessary' and 'contingent' as exercises in logic? Do you propose to instruct me in standard definitions of necessary and contingent as presented in your logic classroom? Then you are making your use of the word 'necessary' contingent on some definitions established in the logic classroom. That's OK with me, too, but this is just an internet forum, a chance for you to try to comminicate clearly what your intentions are. If you have any.
You complained about the way I was using the word 'necessary', so I just wanted to clarify what I meant by the term. But if you already knew what I meant, so much the better. And my intentions? well in this thread I guess that would be to discuss "Reason / Science / Religion" , but as you can probably guess, I'm coming at that from a philosophical bent
You have not made a coherent effort at creating anything but a tautology. Perhaps you mean that a priori knowledge is dogmatic. You still have not shown me how the term should be used 'correctly'. Either make a statement of a priori knowledge, like 'God exists' or some act of mental telepathy, or go home. You haven't even started in with knowledge, let alone gotten to a priori knowledge. You're just using the term because somebody else used it.
examples of a priori knowledge: "2+2=4" "no bachelors are married" "all squares have four sides of equal length" those are knowable a priori, because they can be grasped via reason alone.
Essentially you are saying that self-evident axioms are necessary truths, but you haven't given any examples of such axioms. I would say that self-evident axioms are self-evident, to show you what I mean by 'tautology'.
No I'm not saying that at all. I haven't been talking about self-evident propositions - I believe you brought them up.
And I certainly don't maintain that self-evident propositions are all necessarily true - that is obviously false. for consider: it's self-evident to me that "I exist" is true; however, the fact that I exist is not at all necessarily true, since I could die at any moment. Therefore, just because something is self-evident doesn't mean that it's necessarily true.
"All squares have four sides" is part of the definition of 'squares'. Don't be square, daddy-o, be hip to the jive. It's not 'necessary' that squares have four sides. We could have called them 'frambelisks'. It's not necessary that they have four sides, because you have to define the number '4' first. Perhaps you think that the natural numbers are 'necessary'. You should have said that to start. At least you'd be able to quote somebody famous:
You are confusing a term with what the term stands for. "Square" is the name we give to squares, closed shapes with four sides of equal length. But when one says "all squares have four sides", one is talking about squares themselves, not "squares" their name. It's not the square's name that has four sides, it's the square itself. And you're right, we could have named them whatever we wanted - "Frambelisk" if you like - but they would still have been the same thing, they would still have had four sides of equal length.
"God created the integers," wrote mathematician Leopold Kronecker, "All the rest is the work of Man." Maybe you wish to say something similar about modus ponens. Modus tollens? If you're not metabolising, and created by god, you're not alive.
No I think God has created every existing thing about from himself, but I don't think he created the rules of logic (that seems to be an incoherent idea).
Saying that there are intelligent species in the universe depends on calling whatever we are doing here 'the exercise of reason'. The debate about what part of mathematics is synthetic is actually an ongoing debate among philosophers. I don't know the technical term for this. Instead, I learned how to use mathematics, a very little bit. What we are doing here is the exercise of language. I call that, in context, 'wibbling'.
What I mean is that, if I wanted to learn a conventional set of definitions of necessary, contingent, and a priori, I would go to a university and pay tuition so I could have something on a transcript certifying that I knew something. Been there. Done that.
So much for Aristotle's "ALL men by nature desire to know" (first line of the Metaphysics)
My only interest in defining the terms that I use is so that my interloculars and I don't come to find, after pages of discussion and argumentation back and forth, that our whole disagreement had been based on nothing more than a semantical miscommunication (that's happened more times than I can count). I can assure you - I'd love to go without having to define the same old terms over and over, but then people just talk past one another.