context: It is probably not the case that Bernhard is white. There is a very good chance that Bill went to the garden. It is improbable that John discarded the apple. We doubt that if 'Bill went to the garden and John discarded the apple' then Mary got the milk. We believe that if either 'Bill went to the garden' or 'John discarded the apple' but not both then Brian is a swan. It is probably not the case that if 'John discarded the apple' or 'Bill went to the garden' or both then Jessica is a mouse.
hypothesis: It is highly unlikely that 'Bill went to the garden' or 'John discarded the apple' or both.
valid_hypothesis: There is a very good chance that 'Bill went to the garden' or 'John discarded the apple' or both.
invalid_hypothesis: It is highly unlikely that 'Bill went to the garden' or 'John discarded 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
    0.25::factA.
    0.8::factB.
    0.1::factC.
    %hop1
    0.2::factX:-and(factB,factC).
    0.75::factY:-xor(factB,factC).
    0.25::factZ:-or(factC,factB).
  
    %hop2
    conclusion:-or(factB,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Bill went to the garden' or 'John discarded the apple' or both.