It is probably the case that Yann is tired. It is improbable that Bill went to the garden. There is little chance that Lily is a lion. It is almost certain that if 'Bill went to the garden' or 'Lily is a lion' or both then John dropped the apple. It is probable that if 'Bill went to the garden and Yann is tired' then Mary picked up the milk. We doubt that if 'Bill went to the garden and Lily is a lion' then Winona is a sheep.
It is highly unlikely that 'Yann is tired and Lily is a lion'.
It is highly unlikely that 'Yann is tired and Lily is a lion'.
It is certain that 'Yann is tired and Lily is a lion'.

  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.
  0.1::factB.
  0.1::factC.
  %hop1
  0.95::factX:-or(factB,factC).
  0.7::factY:-and(factB,factA).
  0.2::factZ:-and(factB,factC).

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

  query(conclusion).
  
'Yann is tired and Lily is a lion'.