Difference between Foolish and Rattlebrained

FOOLISH vs RATTLEBRAINED: ADJECTIVE

Devoid of good sense or judgment
Lacking or exhibiting a lack of good sense or judgment; silly.
Capable of arousing laughter; absurd or ridiculous.
Embarrassed; abashed.
Insignificant; trivial.
Marked with, or exhibiting, folly; void of understanding; weak in intellect; without judgment or discretion; silly; unwise.
Such as a fool would do; proceeding from weakness of mind or silliness; exhibiting a want of judgment or discretion.
Absurd; ridiculous; despicable; contemptible.
Lacking good sense or judgement; unwise.
Resembling or characteristic of a fool.
Having or revealing stupidity

Like a fool; manifesting folly; deficient in understanding, sense, or discretion; weak in intellect or judgment; unwise.
Proceeding from or prompted by folly; exhibiting a want of discretion or discrimination; silly; vain; trifling.
Ridiculous; contemptible.
Synonyms Silly, Foolish (see absurd); shallow, brainless, harebrained, simple.
Slight; insignificant.
Denoting or indicative of folly.

Insane, Nonsensical, Unreasonable, Harebrained, Fatuous, Fool, Preposterous, Absurd, Asinine, Ridiculous, Misguided, Ludicrous, Silly, Stupid, Unwise

Saphead, Folliful, Silly, Dotish, Frible, Featherbrain, Idiotish, Vaniloquent, Insipient, Desipient, Glaikit, Rattlepated, Scatterbrained, Foolish, Scatty

Insane, Nonsensical, Unreasonable, Harebrained, Fatuous, Fool, Preposterous, Absurd, Asinine, Ridiculous, Misguided, Ludicrous, Silly, Stupid, Unwise

Saphead, Folliful, Silly, Dotish, Frible, Featherbrain, Idiotish, Vaniloquent, Insipient, Desipient, Glaikit, Scatty, Scatterbrained, Rattlepated, Foolish

Anyone not using the AMEX deal is foolish.
MASTER: That would be very foolish of you.
Are Economic Giants Penny Wise But Pound Foolish?
Baloo knows it; I know it; the Pack know it; and even the foolish, foolish deer know.
So, the preaching of the gospel is not foolish, but the question today is: Is there such a thing as foolish preaching?
You looked foolish the last two times you said it for the previous two contracts, and you will look foolish again this time.
Of all the foolish Fears of Humankind, Fear of the Future is by far the most foolish.
There are no foolish trades, there are only foolish people.
Young and Foolish Young and foolish Why is it wrong to be Young and foolish?
That foolish idea may not be so foolish after all.