A monk once said:
If you’re 37, instead of regretting that you can’t wake up at age 18 again, pretend to yourself that you’re 90 and you’ve woken up at age 37 again, and that you get to magically, wonderfully have the next 50 years again.

A monk suggests that instead of regretting not being 18 again, imagine you’re 90 and magically get to relive your 37-year-old life for the next 50 years. This mindset helps you appreciate the present and the time you have.