Assent--and you are sane--,
Demur--you're straightway dangerous--,
And handled with a Chain--.
Source: The Complete Poems of Emily Dickinson, no. 435, ed. Thomas H. Johnson, 1955.
-- Emily Dickinson, (Dec 10 1830-1886), US poet; She was a reclusive stylist who combined spare lyricism with unorthodox diction.