context: There is a very good chance that Mary went to the bedroom. It is probable that Lily is a swan. It is almost certain that John picked up the apple. It is improbable that if either 'John picked up the apple' or 'Lily is a swan' but not both then Fred is in the school. There is little chance that if either 'John picked up the apple' or 'Mary went to the bedroom' but not both then Winona is a mouse. There is little chance that if 'Mary went to the bedroom and John picked up the apple' then Bernhard is green.
hypothesis: It is probably not the case that either 'John picked up the apple' or 'Mary went to the bedroom' but not both.
valid_hypothesis: It is probably not the case that either 'John picked up the apple' or 'Mary went to the bedroom' but not both.
invalid_hypothesis: It is highly likely that either 'John picked up the apple' or 'Mary went to the bedroom' but not 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
    0.8::factA.
    0.7::factB.
    0.95::factC.
    %hop1
    0.1::factX:-xor(factC,factB).
    0.1::factY:-xor(factC,factA).
    0.1::factZ:-and(factA,factC).
  
    %hop2
    conclusion:-xor(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: Either 'John picked up the apple' or 'Mary went to the bedroom' but not both.