An unsupervised five-year-old will let a stranger indoors, take candy from a stranger, play with a gun he finds etc. no matter what you drill into him.

I don't believe I would have done any of those things - and my parents would agree. Comprehension and implementation of rules was well within the realm of my capabilities and I was only rebellious against or defiant of rules I thought were stupid. Not those that could be explained ("that is dangerous and kills people") or those that I was already indifferent to (I would only have answered the door out of a sense of obligation or kindness anyway, I certainly wouldn't have wanted to.)

"No matter what you drill into him" sets a fairly high bar of stupidity.