What is probable cause for commitment by a magistrate?

Probable cause for commitment by a magistrate is shown 'if there is some rational ground for assuming the possibility that an offense has been committed and the accused is guilty of it'; or, stated otherwise, 'if a man of ordinary caution or prudence would be led to believe and conscientiously entertain a strong suspicion of the guilt of the accused.' (Bompensiero v. Superior Court, 44 Cal.2d 178, 183--184, 281 P.2d 250, 254.)