There is little chance that Sandra got the football. It is probably the case that Julius is a frog. We believe that Brian is yellow. It is impossible that if either 'Julius is a frog' or 'Sandra got the football' but not both then Yann is bored. There is little chance that if 'Brian is yellow' or 'Sandra got the football' or both then Jeff went to the bedroom. It is certain that if 'Sandra got the football' or 'Julius is a frog' or both then Winona is a sheep.
It is impossible that 'Yann is bored and Julius is a frog'.
It is impossible that 'Yann is bored and Julius is a frog'.
It is highly likely that 'Yann is bored and Julius is a frog'.

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

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

  query(conclusion).
  
'Yann is bored and Julius is a frog'.