As an example, that first of all demonstrations, that of Pythagorean theorem : how does the figure prove that in a triangle with a 90° angle, a²+b²=n² ? Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
a2+b2+2ab=2ab+n2
so a2+b2=n2 Life should consist in at least fifty percent pure waste of time, and the rest doing what you please.
At no point in the proof there is a nonhomogenoeous polynomial adding a length to an area, for instance. So Ceebs' argument can be written out in words involving areas.
I think that diagrammatic proof of Pythagoras' theorem may have originated in India? We have met the enemy, and he is us — Pogo
I'm still pondering the idea of an "imageless" maths that invokes images (the diagram above), or a graph--something visual at any rate that stands for...the invisible maths behind the image...
So it may be easy, but easy is good (for me) if it helps me concentrate on the underlying aspect, in this case:
When one advances enough, the pleasures of maths become non-visual ; Maths after all is the art of abstract symbol manipulation.
(Thing is, I have pondered this and I am wondering whether maths' claim to be somehow bigger than the universe (maths gives us "the universe" + 1)--I mean the idea that maths "encompasses" the universe as compared to the universe being "bigger than maths"--Heh, I'll have to try and explain this again later, but I mean something like: "What does it mean that we can't beyond a certain exponential--I was thinking about mathematical models of the universe--there is the "empty box" model, we are in it and the sides are an endless distance away. Then there is the "closed form" model, balls, saddles, but always (inevitably) seen from "outside"...heh...I'll post this just to remind myself that I had a thought in there somewhere. Don't fight forces, use them R. Buckminster Fuller.
Notice that before the development of symbolic algebra in the middle ages, elgebra had always a geometric interpretation. Squares were the areas of squares. Linear quantities were the lengths of segments. Cubes were the volumes of actual cubes. Inhomogeneous polynomials (mixing quantities of different degree) didn't often occur.
Mathematics has always been visual, touchy-feely, intuitive, until the formalization in the 19th century. We have met the enemy, and he is us — Pogo
But this one should be really easy. We had to find this out on ourselves, I don't know, maybe as sixth graders.
I mean the idea that maths "encompasses" the universe as compared to the universe being "bigger than maths"
Do you know that Set Theory proves that there is no Universe?
Then there is the "closed form" model, balls, saddles
Saddles are a representation of open ever-expanding hyperbolic universes. *Traitor*, n. A benighted individual who perceives an illusory distinction between serving his nation and abetting the criminals who govern it.
Logic is how you are allowed to manipulate abstract symbols ; the rest of maths is deciding about some abstract symbol, and then playing with them a lot... Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
In my view N only has the meaning we give it through axioms ; axioms which are rules on how to write proofs.
What do you mean by 'meaning' ? :) Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
Axiomatization is not the prerequisite for mathematics, it's the endpoint. We have met the enemy, and he is us — Pogo
Also, is R more concrete than the set of p-adic numbers? is Euclidean geometry less abstract than other geometries ? Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
R is more concrete than the set of p-adic numbers. That is why it was invented centuries earlier.
And while Euclid and his contemporaries had axioms, mathematics had existed before them. The greeks may have invented the axiomatic-deductive method, but they did not invent mathematics. We have met the enemy, and he is us — Pogo
Which geometry is concrete to a blind person ?*
It seems you define concrete as intuitively accessible to the human brain... It makes god a very concrete concept nowadays. Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
It seems you define concrete as intuitively accessible to the human brain...
As for spherical geometry being invented after euclidean geometry, I don't know what came first, but spherical geometry was highly developed by babylonian astronomers while the Babylonian value for pi was still the integer 3. We have met the enemy, and he is us — Pogo
Also, is there mathematical truth independent of thought processes : is logic only a cognitive process ? Colman was contrasting logics with the rest of mathematics. Is logic "true" because it agrees with our thought processes - but many people think without adhering to the laws of logic. Why would logic be different from the rest of maths ? Auferre, trucidare, rapere, falsis nominibus imperium; atque, ubi solitudinem faciunt, pacem appellant.
Concepts of abstract and concrete can depend where you're looking at them from: N can be relatively concrete. In a moment we can consider what is concrete, precisely.
