It is probably the case that John discarded the apple. There is a very good chance that Julius is a frog. It is highly likely that Brian is green. It is impossible that if either 'Brian is green' or 'Julius is a frog' but not both then Greg is a rhino. There is little chance that if 'John discarded the apple and Julius is a frog' then Bill got the milk there. There is a better than even chance that if 'Brian is green and John discarded the apple' then Emily is a mouse.
It is highly likely that 'Emily is a mouse' or 'Julius is a frog' or both.
It is highly likely that 'Emily is a mouse' or 'Julius is a frog' or both.
There is almost no chance that 'Emily is a mouse' or 'Julius is a frog' or both.

  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.
  0.8::factB.
  0.9::factC.
  %hop1
  0.0::factX:-xor(factC,factB).
  0.1::factY:-and(factA,factB).
  0.6::factZ:-and(factC,factA).

  %hop2
  conclusion:-or(factZ,factB).

  query(conclusion).
  
'Emily is a mouse' or 'Julius is a frog' or both.