context: It is certain that Mary picked up the milk. It is impossible that Gertrude is a mouse. There is a very good chance that Bernhard is a rhino. It is almost certain that if 'Mary picked up the milk and Bernhard is a rhino' then Jessica is a wolf. There is a very good chance that if 'Bernhard is a rhino and Mary picked up the milk' then Lily is a lion. It is likely that if 'Gertrude is a mouse and Mary picked up the milk' then Brian is gray.
hypothesis: We believe that 'Jessica is a wolf' or 'Brian is gray' or both.
valid_hypothesis: We believe that 'Jessica is a wolf' or 'Brian is gray' or both.
invalid_hypothesis: Chances are slight that 'Jessica is a wolf' or 'Brian is gray' or both.
problog: 
    and(A,B) :- A,B.
    or(A,B) :- A;B.
    nand(A,B) :- not(and(A,B)).
    nor(A,B) :- not(or(A,B)).
    xor(A,B) :- or(A,B), nand(A,B).
  
    %hop0
    1.0::factA.
    0.0::factB.
    0.8::factC.
    %hop1
    0.95::factX:-and(factA,factC).
    0.8::factY:-and(factC,factA).
    0.7::factZ:-and(factB,factA).
  
    %hop2
    conclusion:-or(factX,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Jessica is a wolf' or 'Brian is gray' or both.