context: It is probably the case that Mary grabbed the milk. There is little chance that Brian is white. There is a better than even chance that Gertrude is a mouse. It is probable that if 'Gertrude is a mouse' or 'Brian is white' or both then Sumit is tired. It is probably the case that if 'Brian is white' or 'Mary grabbed the milk' or both then John dropped the apple. It is impossible that if 'Gertrude is a mouse' or 'Mary grabbed the milk' or both then Bernhard is yellow.
hypothesis: Chances are about even that 'Gertrude is a mouse and Sumit is tired'.
valid_hypothesis: Chances are about even that 'Gertrude is a mouse and Sumit is tired'.
invalid_hypothesis: It is highly unlikely that 'Gertrude is a mouse and Sumit is tired'.
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
    0.7::factA.
    0.1::factB.
    0.6::factC.
    %hop1
    0.7::factX:-or(factC,factB).
    0.7::factY:-or(factB,factA).
    0.0::factZ:-or(factC,factA).
  
    %hop2
    conclusion:-and(factC,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Gertrude is a mouse and Sumit is tired'.