Ignorance vs. Stupidity vs. Intelligence vs. Development
Ignorance is lacking knowledge that 2+2=4 but aware of it's existence.
Stupidity is not knowing 2+2 existed, dull of the mind, lacking keeness, unaware.
Intelligence is ability to develop the ignoramus mind. Intelligence cannot develop the stupid mind, because there is no intelligence to work with, one cannot be stupid and intelligent at the same time, therefore Stupidity is an unfortunate birth.
Development is constructing the ignorant mind, building it from a foundation of intelligence, not from a foundation of stupidity. Stupidity remains stupid, while intelligence progresses ignorance!
Development begins upon pregnancy conception, and continues to develop upon birth and death.