context: It is impossible that Brian is white. It is probably not the case that John put down the apple. There is a better than even chance that Mary left the milk. It is probable that if 'John put down the apple' or 'Brian is white' or both then Bernhard is a rhino. It is probably not the case that if 'John put down the apple' or 'Mary left the milk' or both then Julius is a frog. Chances are about even that if 'Brian is white and John put down the apple' then Daniel dropped the apple.
hypothesis: It is almost certain that 'John put down the apple' or 'Julius is a frog' or both.
valid_hypothesis: It is probably not the case that 'John put down the apple' or 'Julius is a frog' or both.
invalid_hypothesis: It is almost certain that 'John put down the apple' or 'Julius is a frog' 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
    0.0::factA.
    0.25::factB.
    0.6::factC.
    %hop1
    0.7::factX:-or(factB,factA).
    0.25::factY:-or(factB,factC).
    0.5::factZ:-and(factA,factB).
  
    %hop2
    conclusion:-or(factB,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'John put down the apple' or 'Julius is a frog' or both.