RichThesaurus
dumb as a post
vs
one brick short of a full load
dumb as a post
adj
Extremely stupid.
Utterly mute; lacking the ability to speak.
one brick short of a full load
adj
Stupid.
Not mentally sound; insane.
How often have the words
dumb as a post
and
one brick short of a full load
occurred in a corpus of books?
(source:
Google Ngram Viewer
)