What is the life-changing self-improvement you ever read?

It wasn't something I read, but something I watched. It was a parenting class and the video lecture was talking about what things you should really worry about and what things you shouldn't really worry about with your kids - something related to natural consequences. The key phrase was "if it's not illegal, immoral or life-threatening, it probably doesn't need as much worry". It is something that falls between too extremes - that of the "overly legalistic, rule enforcing, never say yes to anything, never praise for anything" style of parenting and the "laissez-faire, don't stifle their creativity, only give positive responses, do what you want, it's your life" style of parenting (I think this last one is winning these days). Basically, it means that yes, there should be rules and there should be discipline, but you can say yes to more things that aren't really harmful in any way than you do, and you can say no when something will be truly detrimental or cause potential harm. My kids went through a "I don't want to wear a coat" stage. The idea was if they didn't want to wear a coat to school, then so be it. When they got cold, they'd be back. But, if they were going out to the mountains to go camping or outside to play in the snow for long periods of time, then yes - they had to take their coats because too much exposure is a bad thing. My son wanted to wear shorts to school in winter. My mother had a fit. I said, I don't get it - it was OK for us to wear dresses before we were allowed to wear pants to school and the wind could blow up our skirts, but my son can't wear shorts with legs? Sorry, Mom, but he can. If he gets cold, he'll wear longer pants next time. It was like night and day for me - so much less to worry about, focusing on the things that were really harmful and not the things that would be corrected by society in time.