nugget of wisdom
A particular or singular thing that someone has written or said which is especially wise, sagacious, or informative. Can also be used sarcastically to imply that what is said is banal, useless, or uninformative. My uncle loves to give advice, and he's never short of little nuggets of wisdom whenever we go to visit him. Thanks for that nugget of wisdom, Jeff. I'm sure sunbathing tips will really come in handy in Iceland!