It is probably not the case that Sumit is hungry. We believe that Lily is yellow. It is probable that Bernhard is a frog. There is a better than even chance that if either 'Bernhard is a frog' or 'Lily is yellow' but not both then Sandra dropped the milk. It is highly likely that if either 'Sumit is hungry' or 'Bernhard is a frog' but not both then Gertrude is a mouse. It is improbable that if 'Lily is yellow' or 'Bernhard is a frog' or both then Julius is green.
It is probably the case that 'Bernhard is a frog and Sumit is hungry'.
It is unlikely that 'Bernhard is a frog and Sumit is hungry'.
It is probably the case that 'Bernhard is a frog and Sumit is hungry'.

  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.
  0.75::factB.
  0.7::factC.
  %hop1
  0.6::factX:-xor(factC,factB).
  0.9::factY:-xor(factA,factC).
  0.1::factZ:-or(factB,factC).

  %hop2
  conclusion:-and(factC,factA).

  query(conclusion).
  
'Bernhard is a frog and Sumit is hungry'.