foolish idea; poor plan
Used to criticize or dismiss an idea as ill-conceived or unwise. Not necessarily humble; can be used about others' ideas.
Such a foolish idea was immediately rejected.
my humble idea; my humble opinion
Humble expression used to refer to one's own idea or opinion modestly. Often used in formal or self-deprecating contexts.
This is just my humble idea, but what do you think of this method?
Compound of 愚 (gu, 'foolish') and 案 (an, 'plan, idea'). The humble usage arises from self-deprecating reference to one's own ideas.