Law of Excluded Middle/Proof Rule/Technical Note

Technical Note on
When invoking  in a tableau proof, use the ExcludedMiddle template:



or:

where:
 * is the number of the line on the tableau proof where the is to be invoked
 * is the statement of logic that is to be displayed in the Formula column, without the  delimiters
 * is the (optional) comment that is to be displayed in the Notes column.