We doubt that Julius is a lion. It is probably not the case that Greg is a rhino. It is highly unlikely that Sandra got the milk. We believe that if 'Greg is a rhino and Sandra got the milk' then Jeff left the football. There is a very good chance that if 'Greg is a rhino' or 'Julius is a lion' or both then Mary went to the kitchen. It is probably the case that if 'Julius is a lion and Sandra got the milk' then John put down the apple.
We believe that 'Jeff left the football and Mary went to the kitchen'.
It is impossible that 'Jeff left the football and Mary went to the kitchen'.
We believe that 'Jeff left the football and Mary went to the kitchen'.

  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
  0.2::factA.
  0.25::factB.
  0.05::factC.
  %hop1
  0.75::factX:-and(factB,factC).
  0.8::factY:-or(factB,factA).
  0.7::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Jeff left the football and Mary went to the kitchen'.