context: It is highly likely that Brian is a frog. There is a very good chance that John went to the kitchen. It is probably the case that Lily is a rhino. Chances are about even that if either 'John went to the kitchen' or 'Brian is a frog' but not both then Daniel dropped the apple. We doubt that if 'John went to the kitchen' or 'Lily is a rhino' or both then Antoine is hungry. We believe that if 'Lily is a rhino' or 'John went to the kitchen' or both then Mary left the football.
hypothesis: There is little chance that 'John went to the kitchen' or 'Antoine is hungry' or both.
valid_hypothesis: There is a very good chance that 'John went to the kitchen' or 'Antoine is hungry' or both.
invalid_hypothesis: There is little chance that 'John went to the kitchen' or 'Antoine is hungry' 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
    0.9::factA.
    0.8::factB.
    0.7::factC.
    %hop1
    0.5::factX:-xor(factB,factA).
    0.2::factY:-or(factB,factC).
    0.75::factZ:-or(factC,factB).
  
    %hop2
    conclusion:-or(factB,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'John went to the kitchen' or 'Antoine is hungry' or both.