“ lowercase letter represents a constant (could be any kind of constant, like an integer or a string)
An uppercase letter represents a variable”
I already disagree with this syntax.
I already disagree with this syntax.
Prolog does unification of the proof goal with the rule head. It's necessary there but not with datalog.
But I still agree with you about the capitalization. Some formats, like KIF, use a '?' prefix instead, and I've seen some HRF notations that mix the '?' prefix with non-KIF formatting (':-' operator and '.' terminator).