context: It is almost certain that Julius is a lion. We believe that Mary left the football. It is certain that Sandra dropped the milk. It is probably the case that if 'Mary left the football' or 'Sandra dropped the milk' or both then Jeff moved to the garden. We doubt that if 'Sandra dropped the milk and Mary left the football' then Greg is a rhino. There is a better than even chance that if either 'Sandra dropped the milk' or 'Mary left the football' but not both then Emily is a cat.
hypothesis: It is highly likely that 'Mary left the football and Emily is a cat'.
valid_hypothesis: It is impossible that 'Mary left the football and Emily is a cat'.
invalid_hypothesis: It is highly likely that 'Mary left the football and Emily is a cat'.
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
    0.95::factA.
    0.75::factB.
    1.0::factC.
    %hop1
    0.7::factX:-or(factB,factC).
    0.2::factY:-and(factC,factB).
    0.6::factZ:-xor(factC,factB).
  
    %hop2
    conclusion:-and(factB,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary left the football and Emily is a cat'.