We believe that Brian is a lion. There is almost no chance that John went to the garden. It is impossible that Emily is a mouse. It is certain that if 'Brian is a lion' or 'Emily is a mouse' or both then Sumit is thirsty. It is likely that if either 'John went to the garden' or 'Brian is a lion' but not both then Mary picked up the apple. It is highly unlikely that if 'Emily is a mouse' or 'Brian is a lion' or both then Sandra dropped the milk.
It is almost certain that 'Brian is a lion and Mary picked up the apple'.
Chances are about even that 'Brian is a lion and Mary picked up the apple'.
It is almost certain that 'Brian is a lion and Mary picked up 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
  0.75::factA.
  0.02::factB.
  0.0::factC.
  %hop1
  1.0::factX:-or(factA,factC).
  0.7::factY:-xor(factB,factA).
  0.05::factZ:-or(factC,factA).

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

  query(conclusion).
  
'Brian is a lion and Mary picked up the apple'.