There is almost no chance that Jeff dropped the apple. It is probably the case that Jason is thirsty. It is highly likely that Bernhard is yellow. It is impossible that if 'Jeff dropped the apple' or 'Jason is thirsty' or both then Daniel took the football. It is likely that if 'Bernhard is yellow' or 'Jason is thirsty' or both then Winona is a sheep. It is probably the case that if 'Jason is thirsty and Jeff dropped the apple' then John moved to the office.
We doubt that 'Jason is thirsty' or 'Jeff dropped the apple' or both.
It is probably the case that 'Jason is thirsty' or 'Jeff dropped the apple' or both.
We doubt that 'Jason is thirsty' or 'Jeff dropped the apple' or both.

  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
  0.02::factA.
  0.7::factB.
  0.9::factC.
  %hop1
  0.0::factX:-or(factA,factB).
  0.7::factY:-or(factC,factB).
  0.7::factZ:-and(factB,factA).

  %hop2
  conclusion:-or(factB,factA).

  query(conclusion).
  
'Jason is thirsty' or 'Jeff dropped the apple' or both.