[Nadya]

>The underlying point is that not everyone needs a job. "Everyone has a job" is not an important fundamental requirement of functioning society.

The discussion was about whether or not jobs have been lost. Not whether or not jobs will be or are necessary. For the time being, jobs are both being lost and necessary. At least for most people and people who don't enjoy being homeless.

[resu_nimda]

In 1870, nearly half of the workforce worked in agriculture. Almost all of those "jobs" were "lost" over the next century. Did that have a meaningful correlation with unemployment rate?

There is not some fixed amount of "work that needs to be done" that in turn creates a fixed (and steadily diminishing) pool of jobs to draw from. The amount of jobs available is a purely socioeconomic function of who is willing to pay whom for what.

Take Facebook. Do the jobs there carve out some section of the total amount of work that needs to be done today? Not really, a guy made a thing, and convinced people to give him an arbitrary amount of money, and decided to give an arbitrary number of people arbitrary amounts of that money to help him out. A certain number of jobs were created because of the way people decided to distribute their money. Not because they took some of the limited "available job" slots.