It is likely that Mary left the apple. It is certain that Brian is white. It is unlikely that John discarded the milk. There is a better than even chance that if either 'John discarded the milk' or 'Brian is white' but not both then Gertrude is a sheep. It is improbable that if 'Brian is white' or 'Mary left the apple' or both then Bernhard is a frog. It is highly unlikely that if 'Brian is white' or 'Mary left the apple' or both then Jeff went to the garden.
It is likely that 'Jeff went to the garden and John discarded the milk'.
There is almost no chance that 'Jeff went to the garden and John discarded the milk'.
It is likely that 'Jeff went to the garden and John discarded the milk'.

  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
  0.7::factA.
  1.0::factB.
  0.2::factC.
  %hop1
  0.6::factX:-xor(factC,factB).
  0.1::factY:-or(factB,factA).
  0.05::factZ:-or(factB,factA).

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

  query(conclusion).
  
'Jeff went to the garden and John discarded the milk'.