There's a reason slavery was* one of the most energy efficient tecnologies, until it was banned on obvious ethical grounds. * although "Estimates of the number

There's a reason slavery was* one of the most energy efficient tecnologies, until it was banned on obvious ethical grounds. * although "Estimates of the number of slaves today range from around 21 million-29 million to 46 million." https://en.wikipedia.org/wiki/Contemporary_slavery https://en.wikipedia.org/wiki/Contemporary_slavery