context: We doubt that Jason is tired. It is improbable that John took the apple. It is highly likely that Brian is green. It is impossible that if 'Jason is tired' or 'Brian is green' or both then Bernhard is green. It is probably not the case that if either 'Brian is green' or 'John took the apple' but not both then Lily is a frog. It is improbable that if either 'Brian is green' or 'Jason is tired' but not both then Greg is a rhino.
hypothesis: It is impossible that 'Brian is green' or 'John took the apple' or both.
valid_hypothesis: It is highly likely that 'Brian is green' or 'John took the apple' or both.
invalid_hypothesis: It is impossible that 'Brian is green' or 'John took the apple' 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
    0.2::factA.
    0.1::factB.
    0.9::factC.
    %hop1
    0.0::factX:-or(factA,factC).
    0.25::factY:-xor(factC,factB).
    0.1::factZ:-xor(factC,factA).
  
    %hop2
    conclusion:-or(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is green' or 'John took the apple' or both.