The Luddites
Let’s just take a second to reflect on how long the battle against worker automation has been fought. Here’s where the pejorative term “Luddite” comes from:
The Luddites were 19th-century English textile artisans who protested against newly developed labour-replacing machinery from 1811 to 1817. The stocking frames, spinning frames and power looms introduced during the Industrial Revolution threatened to replace the artisans with less-skilled, low-wage labourers, leaving them without work.
Today, a Luddite refers to someone that avoids new technology (you know, that guy still using a pager).
Those who don’t believe in technological unemployment speak of the Luddite Fallacy, which says everything balances out in the end:
Economists apply the term Luddite fallacy to the notion that technological unemployment leads to structural unemployment (and is consequently macro-economically injurious). If a technological innovation results in a reduction of necessary labour inputs in a given sector, then the industry-wide cost of production falls, which lowers the competitive price and increases the equilibrium supply point which, theoretically, will require an increase in aggregate labour inputs.
According to this reasoning, more efficiency means lower prices. Lower prices means consumers have more money to spend on other things. Some of those other things will require more workers as demand rises. Additionally, lower prices means more demand for the original good, and more demand increases the need for workers, transportation to market, tools for production, etc.
Keep in mind that the Luddite Fallacy is a theory, the proof of which would invalidate the theory of chronic technological unemployment. For all we know, the Luddites might have been dead-on correct.