`Say' echos its argument. Its return value is of no interest.
`Truth' echos its argument and returns a TRUE result.
`False' echos its argument and returns a FALSE result.

  Truth 1 && Truth 2   || Say 3   output=12
( Truth 1 && Truth 2 ) || Say 3   output=12

  Truth 1 && False 2   || Say 3   output=123
( Truth 1 && False 2 ) || Say 3   output=123

  False 1 && Truth 2   || Say 3   output=13
( False 1 && Truth 2 ) || Say 3   output=13

  False 1 && False 2   || Say 3   output=13
( False 1 && False 2 ) || Say 3   output=13

Truth 1 ||   Truth 2 && Say 3     output=13
Truth 1 || ( Truth 2 && Say 3 )   output=1

Truth 1 ||   False 2 && Say 3     output=13
Truth 1 || ( False 2 && Say 3 )   output=1

False 1 ||   Truth 2 && Say 3     output=123
False 1 || ( Truth 2 && Say 3 )   output=123

False 1 ||   False 2 && Say 3     output=12
False 1 || ( False 2 && Say 3 )   output=12