(1) In any prosecution for any offence under this Act which requires a culpable mental state on the part of the accused, the court shall presume the existence of such mental state but it shall be a defence for the accused to prove the fact that he had no such mental state with respect to the act charged as an offence in that prosecution.
     Explanation.--In this section, "culpable mental state" includes intention, motive, knowledge of a fact and the belief in, or reason to believe, a fact.
     (2) For the purposes of this section, a fact is said to be proved only when the court believes it to exist beyond reasonable doubt and not merely when its existence is established by a preponderance of probability.]