doronshadmi
Penultimate Amazing
- Joined
- Mar 15, 2008
- Messages
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EDIT:The task at hand is to define the IsComplete operator. Showing us miscellaneous expressions the include the IsComplete operator does not define it.
You need to provide an expression that shows to what IsComplete S is equivalent. Something of the form:
IsComplete S <=> ...
There are two possible states for set y, it can be complete OR incomplete, depending on its relations with its singleton set.
If {y} is not used as a successor of y, then set y is complete.
If {y} is used as a successor of y, then set y is incomplete.
It can also be written as follows:
"If {y}~$y, then y is complete", which is the same as "y is complete if {y}~$y".
"If {y}$y, then y is incomplete", which is the same as "y is incomplete if {y}$y".
Since y can be complete OR incomplete, depending on its relations with its singleton set, the following expression is wff:
(y is complete if {y}~$y) OR (y is incomplete if {y}$y)
That's all we need to know about y, according to its relations with {y} (which is its singleton set).
The following link is a concrete example of what is written above:
http://www.internationalskeptics.com/forums/showpost.php?p=11268767&postcount=1334.
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