Wednesday, May 30, 2012

One screenshot


This is a screenshot from the movie, "ZULU" distributed around 1964.  Awsome film about 19th century South African colonialism conflicts.  All analog.  No digital.

Thursday, May 24, 2012

truth tables



For (A AND B)
 If     A      false   true
---------------------
  B    |      A AND B
false | false false
true  | false true
 
**************************

For (P OR Q)
  If    P      false true
---------------------
  Q    |     P OR Q
false | false  true
true  | true true

**************************

What about the case in which P is false and Q is true? In a sense we have no evidence
about the implication as long as P is false. Logicians consider that in this case the
assertion P IMP Q is true. Indeed, the proposition P IMP Q is considered vacuously true
in the case where P is false,...

For (P IMP Q)

 If   P       false   true
---------------------
  Q     |     P IMP Q
false | true false
true  | ? true

**************************

vacuously true or, "The Emporer's New Clothes", white lies, etc.

"Every element of the empty set is also an element of {1,2}" is said to be true,
when in fact there aren't any elements in the empty set.
**********************************************************************************************

For (A AND B) IMP B
 If   A false true
--------------------
  B     |     (A AND B) IMP B
false | true true
true  | true true
 
...the proposition (A AND B) IMP B is true regardless of what A and B stand for.
ie. a tautology.

Taken without permission from from:

-http://www.cs.cornell.edu/Courses/cs3110/2011sp/lectures/lec13-logic/logic.htm#2

Saturday, May 19, 2012

Laws of Thought

Laws of Thought
  • xmag idea
    Laws of Thought
    • messagebox_warning

      Identity

      Whatever is, is

        Every A is A.

          EXISTS A

            A=A

              A <-> A

    • messagebox_warning

      Contradiction

      Nothing can both be and not be

        Nothing can be A and not A

        Everything cannot both be and not be

        Everything cannot be A and not A

           A IFF A

              A XOR !A

                A >< !A

    • messagebox_warning

      Excluded Middle

      Everything must either be or not be

          Everything is either A or not A.

          Nothing can be neither A nor not A

              A OR (NOT A)

                 A | !A

Sunday, January 22, 2012

Play This 2


Practice can make one's performance better. The recent bout with the computer playing Iagno, (a form of Othello, found on Debian Linux systems.).