In a comment on my earlier post, Bill H. (run75441) mentioned that he thought at first this series on socially necessary labour time (SNLT) would be about Sydney Chapman's theory. That comment stopped me short because I hadn't thought about the connection between Marx's analysis of SNLT and Chapman's theory of hours.
Recall that Chapman argued that competitive pressures would lead employers to prefer hours of work that were longer than optimal for output and that employees would prefer hours of work that would be longer than optimal for their welfare, although shorter than the hours sought by employers. The reasoning behind such suboptimal preferences was that achieving the long-run optima would require short-term risk with uncertain payoffs.
Output and welfare losses can be estimated to be in the ballpark of 10% and 25%, respectively. That would imply that the optimal labour time for output would be around 90% of the allegedly "socially necessary labour time" and the average individually necessary labour time would be around 67% of so-called necessary labour time. These discrepancies, it should be noted, are in addition to the production of surplus value.
The above speculations are complicated by the fact that Marx and Chapman were referring to fundamentally different theories of value. It may be worthwhile returning to this issue after I have completed my review of Marx's SNLT.
Index to all posts on socially necessary labour time.
I will take the opportunity to plug my publication, "The Ambivalence of Disposable Time" in each of these episodes. I am linking to the published journal article. If anyone needs free access to the author's preprint, let me know in comments and I will leave a link there.