This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# Or

 is the logical OR function. It evaluates its arguments in order, giving True immediately if any of them are True, and False if they are all False.
• Or has attribute HoldAll, and explicitly controls the evaluation of its arguments. In the are evaluated in order, stopping if any of them is found to be True.
• Or gives symbolic results when necessary, removing initial arguments that are False.
Combine assertions with ||:
A symbolic disjunction:
A system of equations:
Enter using Esc or Esc:
Combine assertions with ||:
 Out[1]=

A symbolic disjunction:
 Out[1]=

A system of equations:
 Out[1]=

Enter using Esc or Esc:
 Out[1]=
 Scope   (5)
Or works with any number of arguments:
Or is associative:
Or with explicit True or False arguments will simplify:
Or evaluates its arguments in order, stopping when an argument evaluates to True:
The order of arguments may be important:
Symbolic transformations will not preserve argument ordering:
 Applications   (6)
Combine conditions in Mathematica code:
If an argument of Or evaluates to True, any subsequent arguments are not evaluated:
The argument order in Or matters; if the last two arguments are reversed, I is evaluated:
Combine assumptions:
Combine equations and inequalities; Or is used both in the input and the output:
Use to combine conditions:
A cellular automaton based on Or:
Find the area of the union of sets given by algebraic conditions:
This shows the set:
Truth table for Or:
has higher precedence than :
Use BooleanConvert to expand And with respect to Or:
De Morgan's laws relate And, Or, and Not:
Disjunction of conditions corresponds to the Max of Boole functions: