Presumption as to culpable mental state. 35-O. (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 sub-section, “culpable mental state” includes intention, motive or knowledge of a fact, or 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.