Date: Jan 29, 2013 8:07 PM
Author: Graham Cooper
Subject: [BACKWARD CHAINING is to LOGIC]   as  [INTEGRATION is to CALCULUS]

BACKWARD CHAINING in LOGIC!

It's a very simple concept..

F -> G

G?

to Prove G is True look for an axiom that implies, implies, implies G!


F->G
F
---
G


--------------------------

Example 2

F -> G -> J
F

is J true?


============================

f(1,6)
f(1,7)
f(1,X) -> g(3,X)

is g(3,3) True?

is g(3,7) True?

---------------------

f(1,7) -> g(3,7)
f(1,7)
-------
g(3,7)   is True!


=========================

Now a bit harder!!

( f(X) & g(X) )  ->  j(X)

f(1)
f(2)
f(3)
g(3)
g(4)
g(5)

what value of  j(?)  is true?

---------------------

( f(3) & g(3) )  ->  j(3)
f(3)
g(3)
( f(3) & g(3) )     from above 2 lines
--------------
j(3)  is true!

SCI.LOGIC is not a history literacy group!

We solve predicates around here!

Herc
--
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