- In Praise of Idleness By Bertrand Russell, 1932: http://www.zpub.com/notes/idle.html
- makes the interesting argument that in WWI, a lot of people who would usually be workers had their labor diverted to the war, yet we survived. Therefore at least that much proportion of total labor could be permanently diverted to leisure (this argument does not take into account how many other workers might have had more leisure but spent more time working due to the war; but i suspect this latter quantity is less than the first and hence that the argument as a whole holds)