Non-stupid people always underestimate the damaging power of stupid individuals. In particular non-stupid people constantly forget that at all times and places and under any circumstances to deal and/or associate with stupid people infallibly turns out to be a costly mistake.
(fourth basic law)
Through centuries and millennia, in public as in private life, countless individuals have failed to take account of the Fourth Basic Law, and the failure has caused mankind incalculable losses.