Re: where do I think wrong

On 15/03/2014, at 1:26 AM, Roelof Wobben wrote:
>> 
> 
> No, that was is this one: X /== Y. 

You see to have trouble telling / and \ apart.
It's \==
> 
> Im talking about this one :  	
> ;   same_mother(X, Y),  <- have the same mother and
> \+ same_father(X, Y)  <- is not equal to the same father.
> ).

"Is not equal to the same father"?  What does that mean?
The test is "DO NOT HAVE the same father".
> 
> What if father is divorced and marry another female.
> Then the father is the same but the mother not.

Where in ANY of this code does it say ANYTHING about
marriage?

Two people are
 - full siblings if they have the same father and the
   same mother (whether the parents were married or not)
 - paternal half siblings if they have the same father
   but not the same mother
 - maternal half siblings if they have the same mother
   but not the same father
 - half siblings if they are paternal or maternal
   half siblings.