John said, "If yesterday was tomorrow, today would be Friday."

When did John make this statement?

Wednesday

There is two way to interpret this.
A) If z + 1 ==> z - 1
Then
z ==> z - 2
z - 2 = Friday
z = Sunday

B)If z - 1 ==> z + 1
Then
z ==> z + 2
z + 2 = Friday
z = Wednesday

Option B) makes sense and hence the answer.