How do you mix GTD with daily, weekly, monthly, and quarterly plans?

I'd like to follow up on what bcmyers2112 wrote. As a college professor, I have had some difficult discussions with young people when they wanted to discuss issues related to fertility and reproduction. Unsolicited questions to anyone, even a close friend, in person, alone, about such issues is inappropriate. Discussing such issues in front of a third party can bring pain to that person as well. I know we seem like a hardened lot of ardent GTD'ers who can deal with anything, but there are areas of our lives that are deeply personal.
 
If you are a farmer, it's understandable. Why do you have 50, 100, and 500 year plans? Plans for your children? Do you expect to gain some form of biological immortality at some point in your life?
Some GTDers have plans that are beyond "I", "my", "my children" etc. Let's not forget that one of the highest horizon questions on the personal level can be "Why am I on this planet?".
 
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