???, ??? ?? ????? ?? ????????? ????? ???? ????? ?????? ?????? ?? ????????? ??????? ??????? ?????? ?? ????? ??????.???? ????? ????????? ????? (???? ????? ??????) ???? ????? ?? ???? ????? ?????? ???.But, compared with other industries where “experts” may be controlled by exams, certifications and a governing overall body, any person can study ple