“Seven Deadly Sins

Wealth without work
Pleasure without conscience
Science without humanity
Knowledge without character
Politics without principle
Commerce without morality
Worship without sacrifice.”
― Mahatma Gandhi

The difference between school and life? In school, you're taught a lesson and then given a test. In life, you're given a test that teaches you a lesson.

There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.