The question isn't whether automation decreases the amount of work neccessary to produce the same output, obviously it does. The question is whether we can reallocate workers somewhere in the economy so that we can produce even more output with the same input.
For example, in the U.S. starting from 1917, the great majority of jobs have disappeared, the population (and thus the workforce) has tripled, and yet unemployment is less than 5%.
If you find a way to do something more efficiently, then that creates more wealth for buying things from the former employee's next job. (The problem, not to be overlooked, is that while the economy as a whole benefits, individuals can suffer greatly.)
Yes it is. The amount of consumption (goods and services) a given person can indulge in has an upper limit. In the past, people who were freed from some tasks were simply reallocated to others and more stuff was produced which there was demand for.
Why? What is the limit? The amount can grow, and the evidence that it does is overwhelming.
> In the past, people who were freed from some tasks were simply reallocated to others and more stuff was produced which there was demand for.
Why would that only be 'in the past' and not today and tomorrow?
I alluded to that in my last sentence. You can only reallocate workers to something else if there is demand for that something else. As I said to another poster, there is an upper limit to consumption so at some point there just won't be anything else for people to do/produce. Consumers have an upper bound on their consumption based on the number of hours in a day.
But pointing out a limit in the amount a single person can consume doesn't change the essential situation. It simply means that instead of reallocating worker time to different production, people's time is reallocated to consumption.
If those who have jobs have enough money to hit the limit on what they can (or choose to) consume, they will cease working, leaving those jobs to others.
Well, people out of work can't really allocate their time to consumption. This is the basis for an argument that we need a shorter work week and a need to enforce it (high Europe, screw you US tech industry). When we are efficient enough to provide everything people want to consume in their 24 hour day and have leftover people without work, we need to make them work less so it will require more people to do all the work. I think there are limits to that as well.
These problem all lie on a path to a possible utopia where the machines take care of the people and we're free to do whatever we want. I'm not sure how you get there from here or what that would even look like.
However, I do not think we will have to force people to work less. If someone has hit the limit of what they want to consume, why are they still working? If there is really nothing more that money can buy, why would they be trying to earn more money?
Automation transfers an increasing share of returns of economic activity to the capitalist owning the automated tool from labor; "destroys jobs" may be a result, but increasing (in the absence of some compensatory mechanism) economic inequality is a more certain result.
I think where we are going is this: early days:
Twenty first level, ten second level, maybe five third level.
Future with AI and smart bots: maybe one first,none second, one extreme highly paid third level.
What do you do with the rest?
The notion of replacing low-skilled jobs with high-skilled, better paying ones is true. However since the TCO to the one purchasing the automation is LOWER it says a lot about the total number of people to maintain the system.
This of course neglects any secondary effects where lower costs may increase volume and wider use of the product. But to a first approximation automation destroys jobs. Obviously.