Uncovering the Flaw: A Critique of the Proof of 1 > 0 Using Trichotomy Axiom

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Homework Help Overview

The discussion revolves around a proof attempting to establish that 1 > 0 using the trichotomy axiom and basic axioms of arithmetic. Participants are critiquing the validity of the proof presented in a linked document, which leads to contradictions when assuming different relationships between 1 and 0.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants explore the implications of assuming 1 = 0, 1 < 0, and 1 > 0, noting contradictions that arise from these assumptions. They question the validity of steps in the proof, particularly regarding the additive identity axiom and the treatment of equality.

Discussion Status

The discussion is ongoing, with participants providing insights and critiques of the proof's logic. Some have offered clarifications on axiomatic definitions and the implications of the trichotomy axiom, while others express uncertainty about the validity of their reasoning and the proof's conclusions.

Contextual Notes

Participants reference fundamental axioms of arithmetic and express concern over the potential for flawed reasoning in the original document. There is an acknowledgment of the complexity of the topic and the need for careful examination of assumptions made in the proof.

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There is a proof in this document:

http://docs.google.com/viewer?a=v&q...pPBSj7&sig=AHIEtbSAu9399TLl5Ysmu2o_LwCOymEFxA

trying to prove that 1 > 0 by just using the trichotomy axiom
and the basic other axioms.

The proof is to test whether 1 > 0, 1 < 0 or 1 = 0.
If we assume 1 = 0 then if we invoke the
additive identity axiom
a + 0 = a
a + 0 = a + 0
a + 0 ≠ a + 1

So 1 ≠ 0

By the document, if we assume 1 < 0
1 + (-1) < 0 + (-1)
0 < - 1
0 • (-1) < (-1)•(-1)
0 < 1
But 0 < 1 contradicts the assumption that 1 < 0.

The document then says it must be that 1 > 0 by
the trichotomy axiom.

BUT!

If we had assumed 1 > 0,
1 + (-1) > 0 + (-1)
0 > - 1
(0)•(-1) > (-1)•(-1)
0 > 1
BUT THIS CONTRADICTS OUR ASSUMPTION
THAT 1 > 0

Tell me this is a joke?

I know about the sign change is supposed to occur
when we multiply by (-1) but the PDF
doesn't seem to know this, in fact if we
do the sign change then by the method
I've used we can show:

By the document, if we assume 1 < 0
1 + (-1) < 0 + (-1)
0 < - 1
0 • (-1) < (-1)•(-1)
0 > 1

Which was our assumption to begin with, it satisfies everything
(which is totally bogus).

I must be missing something, I mean a random PDF off the net
couldn't have bad information in it, could it? :rolleyes:

I guess I don't know how to "prove" this, and it's probably not something
you can prove but seeing as the PDF raised the question some pointers
would really help!


(A gift)

https://www.youtube.com/watch?v=FZgKheUt_SU
 
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Things fall apart right from the git-go. If you assume that [itex]0 = 1 [/tex]<br /> then ina + 0 = a <br /> a + 0 = a + 0<br /> a + 0 ≠ a + 1<br /> <br /> the final line doesn't make sense - you can't say the two sides are different after you assume 0 = 1.[/itex]
 
If zero equaled 1 we'd have:

2 + 0 = 2

But 2 + 1 = 3

How can 2 + 1 = 3 and 2 + 1 = 2?

0 is axiomatically defined as the additive inverse of every element in the set so I
was simply showing that we can't assume that 1 = 0, notice the trichotomy axiom
forces us to consider either 1 > 0, 1 < 0 or 1 = 0 & by simply showing that assuming
1 = 0 at all breaks the additive identity axiom. Therefore we can discount that aspect
of the proof and try 1 > 0 and 1 < 0.
 
You missed my point. At the start the assumption was made that 1 = 0 ("If we assume 1 = 0..." so that from that point on those two symbols represent the same object. But later
there is

a+0 = a+0
a+0 /= a+1

where, apparently, the claim of non-equality is made simply because 1 was substituted for 0 and 1 itself is not equal to 0. But, because of the original assumption, there is no valid reason to do that shown in the ``work'' .

I'm not sure what you mean that 0 is the additive inverse of the elements.
 
Hmm, I know what you mean, I guess I should approach this differently then.

Well, first off what I mean by additive inverse was the field axiom

a + 0 = a, basically I'm working off the fundamental axioms:

Closure:
If a,b ∈ P, (a + b) ∈ P (for some set P)
If a,b ∈ P, a•b ∈ P

Commutativity:
a + b = b + a
a•b = b•a

Associativity:
a + (b + c) = (a + b) + c
a•(b•c) = (a•b)•c

Identity:
a + 0 = 0 + a = a
a•1 = 1•a = a

Invertability:
a + (-a) = (-a) + a = 0
a•a-¹ = a-¹•a = 1

Distributivity:
a•(b + c) = a•b + a•c

Trichotomy:
Only one of the following holds:
a = 0, a < 0, a > 0

Basically I was trying to show that if we assume 0 is equal to 1 we reach a contradiction
because if we invoke the additive identity axiom above, that a + 0 = a, we reach a
contradiction because a + 0 is not the same as a + 1, i.e. 2 + 0 is not the same as
2 + 1.

Honestly I initially thought it was just a consequence of the trichotomy axiom but
seeing as this proof was proving something so fundamental I thought maybe this
was a valid way to show why 0 couldn't be 1, obviously not :-p

As for the rest of the proof, does what I've written above hold or have I missed something?
 

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