More Fruits of Solitude by William Penn (1718) Part 4 62-79 (Of the Government of Thoughts)
Bonus:
Summary: Thinking is hard work.
Commentary:
66. To this also is to be attributed the imperfect Knowledge we have of Things, and the slow Progress we make in attaining to a Better; like the Children of Israel that were forty Years upon their Journey, from Egypt to Canaan, which might have been performed in Less than One.
It's amazing how much easier it is to learn a ton of depth about something once you've got the basics down.
69. Always remember to bound thy Thoughts to the present Occasion.
70. If it be thy Religious Duty, suffer nothing else to Share in them. And if any Civil or Temporal Affair, observe the same Caution, and thou wilt be a whole Man to every Thing, and do twice the Business in the same Time.
Multitasking is bullshit.