Madness
Part of speech: noun
Definition: The state of being mad; insanity; mental disease. rash folly
Example sentence: It is madness for sheep to talk peace with a wolf.
Folly
Part of speech: noun
Definition: foolishnessthoughtless action resulting in tragic consequencea fanciful building built for purely ornamental reasons
Example sentence: Humanity has the stars in its future, and that future is too important to be lost under the burden of juvenile folly and ignorant superstition.