It is probably the case that John took the apple. It is highly unlikely that Gertrude is a wolf. It is probably not the case that Bill moved to the office. It is highly likely that if 'John took the apple and Gertrude is a wolf' then Julius is yellow. Chances are slight that if either 'Bill moved to the office' or 'Gertrude is a wolf' but not both then Brian is gray. It is unlikely that if 'Gertrude is a wolf and Bill moved to the office' then Winona is a mouse.
It is highly unlikely that 'Gertrude is a wolf and John took the apple'.
It is highly unlikely that 'Gertrude is a wolf and John took the apple'.
It is probably the case that 'Gertrude is a wolf and John took 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
  0.7::factA.
  0.05::factB.
  0.25::factC.
  %hop1
  0.9::factX:-and(factA,factB).
  0.1::factY:-xor(factC,factB).
  0.2::factZ:-and(factB,factC).

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

  query(conclusion).
  
'Gertrude is a wolf and John took the apple'.