https://news.ycombinator.com/item?id=3995615 https://news.ycombinator.com/item?id=3995615 (both article and comments) describe various ways of looking at this -

https://news.ycombinator.com/item?id=3995615 https://news.ycombinator.com/item?id=3995615 (both article and comments) describe various ways of looking at this - and there are many implications for machine learning e.g. https://news.ycombinator.com/item?id=3995964 https://news.ycombinator.com/item?id=3995964 !