Seems there actually is a fair amount of research pointing to prohibiting corporal punishment for kids leads to better mental health, lower suicide rate, etc. and it does seem like a no-brainer to me that less violence leads to more stable individuals, and a more stable and happy society in general. In medieval times there was a lot of physical punishment, and society was violent, dangerous and unhappy compared to now. Singapore may be modern in many respects, but in this area, they're a bit of a backwater.