But Nyerere’s personality was irresistible. Absolute power never corrupted him. He always obeyed traffic laws when driving around Dar es Salaam, stopping at traffic signals; earned $8,000 a year in pay during his best year, and forgot to collect a government pension. His chosen honorific was Mwilimu, which means teacher; his great moments were articulating an idealistic post-independence vision for Africa. He won victories that have no price tag–under his direction the country adopted one language, Swahili, and defeated a neighboring tyrant, Idi Amin of Uganda. The national literacy level rose sharply. Nyerere was on the right side of every fight in the region. And he never gave up helping. Even after he fell ill with leukemia, he continued to try to broker peace in neighboring Burundi. When Nyerere died last week in London at age 77, the world lost a man of principle.