25% of test subjects show sadistic tendencies.
I'm surprised it's as low as 25%, but they only tested for liking to hurt insects. I suspect that the proportion would be a good bit higher for liking to hurt mammals, and likewise for liking to hurt low-status humans, and possibly for liking to lower the status of high-status humans.
Implications for CEV?
This is why we need nonfeeling robots we can kick around
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.