Jermaine Jackson -- Paris Jackson Needs Discipline

Paris Jackson does NOT respect authority ... so says her uncle Jermaine Jackson ... who insinuated that P's cutting incident was an overreaction to being told she couldn't go to a concert.

TMZ broke the story ... Paris was hospitalized last month for slicing her arm with a meat cleaver ... after she became upset at being told she was not allowed to attend a Marilyn Manson concert.

Sources say Paris' issues stem from her father's death -- which she's had a very hard time dealing with ever since he passed in 2009.

But when we ran into Jermaine in Calabasas yesterday, he told us ... issues be damned, Paris still needs to learn she can't always do whatever she wants.

"[Paris] has to learn there are certain guidelines when you grow up being a teenager," Jermaine said ... "There are rules."

But Jermaine isn't just pointing the finger at Paris ... suggesting P's guardians are to blame -- "I just think that ... things could have been enforced a little stronger."