context: It is probably not the case that Gertrude is a sheep. There is a better than even chance that Brian is a frog. There is a better than even chance that Sandra got the football. It is likely that if 'Brian is a frog and Sandra got the football' then Jeff moved to the office. There is a very good chance that if 'Gertrude is a sheep' or 'Brian is a frog' or both then Jason is bored. It is probably not the case that if 'Gertrude is a sheep' or 'Brian is a frog' or both then Bernhard is a rhino.
hypothesis: It is probably not the case that 'Bernhard is a rhino' or 'Jeff moved to the office' or both.
valid_hypothesis: It is probably not the case that 'Bernhard is a rhino' or 'Jeff moved to the office' or both.
invalid_hypothesis: It is probable that 'Bernhard is a rhino' or 'Jeff moved to the office' 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.
    0.6::factB.
    0.6::factC.
    %hop1
    0.7::factX:-and(factB,factC).
    0.8::factY:-or(factA,factB).
    0.25::factZ:-or(factA,factB).
  
    %hop2
    conclusion:-or(factZ,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Bernhard is a rhino' or 'Jeff moved to the office' or both.