context: Chances are about even that Mary dropped the apple. It is likely that Fred is in the cinema. There is a very good chance that Jessica is a mouse. We doubt that if either 'Jessica is a mouse' or 'Fred is in the cinema' but not both then Lily is a rhino. There is little chance that if 'Jessica is a mouse and Mary dropped the apple' then Julius is a swan. It is probably the case that if 'Fred is in the cinema' or 'Mary dropped the apple' or both then Greg is gray.
hypothesis: It is almost certain that 'Fred is in the cinema' or 'Jessica is a mouse' or both.
valid_hypothesis: It is almost certain that 'Fred is in the cinema' or 'Jessica is a mouse' or both.
invalid_hypothesis: It is unlikely that 'Fred is in the cinema' or 'Jessica is a mouse' 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
    0.5::factA.
    0.7::factB.
    0.8::factC.
    %hop1
    0.2::factX:-xor(factC,factB).
    0.1::factY:-and(factC,factA).
    0.7::factZ:-or(factB,factA).
  
    %hop2
    conclusion:-or(factB,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Fred is in the cinema' or 'Jessica is a mouse' or both.