Not exactly profound, but the link may help:
1. Begin with the end in mind
2. You have no obligation to write an important or even useful thesis
4. Exercise regularly
5. Enjoy your “play time”
6. Talk to others about your problems
7. Record your progress
8. Don’t find excuses - don’t do too many other important things.
9. Choose a dissertation topic you are passionate about
10. Work on your strengths, not on your weaknesses
11. Take charge - it’s your life not your supervisor’s
12. Do what is right for you - including the choice of discontinuing your Ph.D.
See what else they have to say.