context: It is probably not the case that Sumit is thirsty. It is certain that Fred went to the garden. It is impossible that Brian is a frog. It is probably not the case that if either 'Brian is a frog' or 'Fred went to the garden' but not both then Mary moved to the office. There is a very good chance that if 'Brian is a frog' or 'Sumit is thirsty' or both then John put down the apple. It is almost certain that if 'Fred went to the garden and Sumit is thirsty' then Sandra dropped the milk.
hypothesis: It is almost certain that 'Brian is a frog' or 'John put down the apple' or both.
valid_hypothesis: We doubt that 'Brian is a frog' or 'John put down the apple' or both.
invalid_hypothesis: It is almost certain that 'Brian is a frog' or 'John put down 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.
    1.0::factB.
    0.0::factC.
    %hop1
    0.25::factX:-xor(factC,factB).
    0.8::factY:-or(factC,factA).
    0.95::factZ:-and(factB,factA).
  
    %hop2
    conclusion:-or(factC,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is a frog' or 'John put down the apple' or both.