Math Forum / Mathematics / Mathematical Logic / November 2007

I recently completed an Intro to Logic course (using C. Stephen
Layman's The Power of Logic) and a Symbolic Logic course (using
Virginia Klenk's Understanding Symbolic Logic). However, that's the
end of the logic courses in my college! So, could someone recommend me

Einstein's E=mc2 Generalized
is based upon the fact, that Einstein's Sep. 1905 derivation of L=mc2
(light energy mass equivalence), is true under SPECIAL CONDITIONS ,
not in general.

A universe without objects has no distinctions. The number of objects
is  0.
A universe with one object has no distinctions. The number of objects
is 0.

Actions (or efforts) may be divided into primary and secondary; and
between the two are actions which may be described as neutral.  The
idea of neutral effort has a special significance, and refers to a
state of equanimity in action.  There is no contradiction in this, and

As I understand it, first order logic in general is not decidable.
However various fragments of FOL are decidable. There's a
decision procedure if all predicates have arity 1, for example.
Are there other fragments of FOL that are decidable?

Do physicists totally and completely misunderstand General Relativity?
Also, an insight into 4-d (as space + time.)
   http://bhanwara.blogspot.com/
The October entry.

Tautologies and AntiTautologies
                                             ~v~~
Two years ago I offered the subject of tautologies as the fundamental
mechanism of logical operations and a few months back Bob Kolker

Recently, i heard rumours that not Goedel, but von Neumann was the first
to come up with the second incompleteness theorem. Allegedly, when
Goedel presented the first incompleteness theorem, it was von Neumann
who realized that the second theorem was a direct consequence.

In the fresher's maths tutorial, Eddie upset everyone by claiming
"The largest number is 9. I know, because I counted it on my fingers.
If anyone claims that there is a larger number then the claim is
false."

ATTENTION: George, Moeblee, Marshall, Jan Burse and any others who may
be having at least 1% interest in NAFL.
The failure of the law of non-contradiction is very important and
further discussion of NAFL would be meaningful only after this failure

The following (see exposition below) is a class theory that is an
extension of Ackermann's class theory.
This theory contains classes only, so there are no ur-elements.
Classes might be sets or proper classes.

In a previous thread in this usenet- topic: V , Rupert has defined
inaccessible cardinal in the following manner:
x is inaccessible cardinal <->
Ay(y subnumerous to x->(Az((there exists a surjection from P(y) to z)-

This is a little investigation into the nature of modern logics
and(argued) their Aristotelian heritage:
What do the signs of logic and mathematics represent? The ideas of
self-identity, order, space, time, sequence, set, etc., cannot be

Contrary to what some posters have stated in a recent thread on
impredicative sentences in Gödel's proof, there is no self-referential
proposition involved in it.
Let's consider the well known Gödel's sentence G.

Peter smith points out that Godel
1  uses a symbol &#8801;  to have its customy meaning in the first part of
his proof ie biconditional
but then in the second part he has  &#8801; to mean &#8801; as well as =