Sigmund Freud (1856–1939). Beyond the Pleasure Principle. 1922.
The word Unlust, as in the phrase pleasure-pain principle, has been translated as ‘pain’; pain without inverted commas signifies Schmerz in the original. The word Besetzung (literally: state of being occupied), as in the expressions Besetzungsenergie and Energiebesetzung has been rendered by the words ‘investment’ or ‘charge’, the latter being taken from the analogy of electricity. These and other technical terms will be discussed in a Glossary which it is intended to publish as a supplement to the International Journal of Psycho-Analysis.