He was a German social scientist, author, political theorist,
philosopher, and father of Marxist theory, together with Karl Marx.
In 1845 he published "The Condition of the Working Class in England",
based on personal observations and research in Manchester.
In 1848 he co-authored "The Communist Manifesto" with Karl Marx, and
later he supported Marx financially to do research and write "Das
Kapital".
After Marx's death, Engels edited the second and third volumes.
Additionally, Engels organized Marx's notes on the "Theories of Surplus
Value," which he later published as the 'fourth volume' of "Das Kapital".
He has also made important contributions to family economics.
