It is probably not the case that Bernhard is green. There is a better than even chance that Mary went to the office. It is probably the case that John moved to the garden. Chances are about even that if 'Mary went to the office' or 'Bernhard is green' or both then Sandra dropped the apple. There is little chance that if either 'Bernhard is green' or 'John moved to the garden' but not both then Julius is gray. It is probably not the case that if 'John moved to the garden and Mary went to the office' then Brian is white.
We believe that 'Mary went to the office and Sandra dropped the apple'.
It is probably not the case that 'Mary went to the office and Sandra dropped the apple'.
We believe that 'Mary went to the office and Sandra dropped the apple'.

  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.
  0.7::factC.
  %hop1
  0.5::factX:-or(factB,factA).
  0.1::factY:-xor(factA,factC).
  0.25::factZ:-and(factC,factB).

  %hop2
  conclusion:-and(factB,factX).

  query(conclusion).
  
'Mary went to the office and Sandra dropped the apple'.