Dude, you can't even reasonably calculate the number of man-hours that have been lost to air-powered hammers when used to frame a stick-and-nail framed house. Or the number of man-hours lost to power saws (over using a hand-saw). Or in other industries, the number of man-hours lost to software developers as we transitioned from punch cards to having our own desktop computers, or the number of man-hours lost as we transitioned to better IDEs which allow us to more quickly find and fix problems in our software.
Or take the production of films. Can you reasonably calculate the number of man-hours lost when movie makers transitioned from cellulose film stock to using Red cameras and an all-digital production process?
And part of the reason why you cannot say what has been lost is because two things happen when automation takes people's jobs. Prices for a thing go down, but also, money is available to expand the offerings we get. Houses get bigger. Software gets more complex and more intricate. Movies contain more special effects and become "grander" and on a larger scale.
The real problem I have with the reasoning used by those who assume increased productivity (which is what "robots" give us) is that they assume, like Charles Duell's apocryphal quote from 1899 presumes, that everything that can be invented has been invented, and that life will continue on pretty much the same, with the same offerings, same products, same goods and services--but just with fewer people doing them. It's zero-sum thinking--and from an economics perspective, zero-sum thinking has been the source of pretty much most of the evils of the past century.
Remember: whatever happens, whenever anything changes there are always winners and always losers. It doesn't mean we should do nothing, however: doing nothing is a choice with its own array of winners and losers. Remember: millions and millions of low-paid, low skilled jobs were lost in the shift from an agrarian to a manufacturing economy.
What matters is how it affects the overall population as an aggregate. To decide not to act because you're afraid automation will drive lower-paid workers out of the marketplace is to decide to stall wealth creation because you're afraid the wealthiest will benefit.
My understanding was that the $75,000 (or €75,000) cap was a statistical average across regions with varying levels of cost of living and across varying groups of people--including those who definitely report greater levels of happiness and those who do not. And my impression was that the structure of the questionnaire was capturing the happiness which comes from socio-economic stability: at around $75,000, on average, you have achieved a degree of socio-economic security which means you are no longer worrying about where your next meal is coming from, if the roof over your head will be there next year, how you're going to pay for the kid's clothes, and if you can afford a vacation. (And as that number rises, the cost of the vacation or the car or the clothes may increase--but the fact that you will have access to them at some level does not.)
Meaning if you suddenly found yourself flooded with riches, and you are not able to use that money to find happiness, learn to shop better.
One place where I see a 3D printer being of use is when repairing things with hard-to-obtain parts. But of course you can't do this unless you have a database of parts you can print for the thing you are repairing. So like MP3 players (which did not explode until there was a database of downloadable songs that you could buy for 99 cents), we need a database of 3D printable parts for things like dishwashing machines and refrigerators and the like which can be downloaded for relatively cheap and printed on your printer which can be used to fix the broken component.
Of course not all parts can be replaced like this. But certainly there are plenty of components (such as the plastic drive gears in a garage door opener) which can be printed and replaced by consumers.
At the higher end I can see companies like auto repair shops using professional or pro-consumer level printers for printing harder, and more refined components for auto repairs, and even using 3D subtractive technologies (like CAD-driven lathes and CAD-driven milling machines) for making metal components which fail that do not require tight tolerances.
I think where things like the MakerBot gadget failed was that it seemed to be oriented around the idea that everyone could design their own components. But even in today's environment there are far fewer mechanical engineers and designers than folks like that give credit for.
By the way, my own personal feelings are conflicted here. On the one hand I can understand a baker who may not wish to participate in a gay wedding by baking a wedding cake, or a company like Twitter not carrying the President Elect's messages on their platform; forcing them to participate means in order to do business they cannot be selective about their customers. On the other hand, I do find it despicable that a customer would be discriminated against for something as personal--but ultimately inconsequential to the greater public good--as one's own sexual orientation or political beliefs.
In this case I believe the baker or the message aggregation company may hold to their own personal beliefs, but should then suck it up and perform the work realizing they are performing a sort of public service. I have less patience for the baker in this case, only because Christian faith teaches one to love the sinner while hating the sin--meaning if they believe homosexuality is a sin (I don't, BTW), they still need to forgive the sinner and to act gracefully. (I'm reminded of the story of a bunch of Jewish rabbis who visit a farmer to slaughters his prized pig in order to celebrate the visit. As the story goes, the rabbis eat the prepared pig because acting graceful in this situation supersedes the requirement to keep kosher.)
It's sad that we now live in an era where gracefulness is no longer respected, emulated or even acknowledged in the public sphere. And to me it's sad that Twitter responds to President-elect Trump's apparent lack of grace by doubling down on being even less graceful.
As it turns out, for the purposes of hiring and firing, political orientation is a protected class in some states, such as California. Which is why the CEO of Grubhub had to backtrack from his original e-mail to employees asking Trump supporters to resign.
In the case of Twitter, I'm not sure if they aren't already exposed to some legal consequences for their decision--however, I'm not seeing the AG of California stepping up and doing anything here, since it's pretty clear in this political climate we're slowly turning all of these tools (both legal and technological) into weapons to bash the opposition--generally the right, as most tech companies both reside in liberal areas and tend to lean liberal themselves.
However, given the problems Twitter seems to be having as a business (being unable to monetize its audience without breaking the platform), I suspect pissing off half your audience is not going to help the bottom line--and ultimately Twitter may find itself on the losing end of free market competition.
Does a bakery, as a private company, have the right to say "No cakes that we don't like"?
Actually, it depends on the state where you live. Legal Zoom observes that there are about 20 states in the United States which have anti-discrimination laws based on sexual orientation, so if you are in one of those states, as a practical matter (rather than as a moral one) you cannot discriminate against a gay couple wanting a wedding cake for their gay marriage. However, you can discriminate against a skinhead group from wanting a swastika on their cake, since membership in a skinhead group is not a protected class.
That's akin to saying I wonder who would win a football game if we awarded points for things like field goals and touchdowns differently--without realizing that by altering the point system, you alter the behavior of the players on the field.
There are plenty of places in California--a solidly Democratic state which is highly unlikely to vote for a Republican candidate anytime soon--where a popular vote scheme would yield plenty of votes for a Republican candidate, such as through the San Joaquin Valley.
A quick check of Wikipedia would tell you what most people who follow Apple already know: that Apple has a habit of quietly revving its current computers without much fanfare, upgrading their computers on a regular basis.
The current 13 inch and 15 inch MacBook Pros that Apple sell were last updated early 2015. (This correlates with Apple's own on-line store.)
It's not to suggest their current models aren't a little long in the tooth. And it's not to suggest that Apple may be a little behind in using the latest and greatest processors--though one problem Apple has is that they sell quite a bit of volume, so sometimes being on the bleeding edge may not permit them to get the volume of parts they need. But they most certainly are not selling a 4 year old computer.
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