I agree with Darwin’s combination of rocks, thinking, and walking, they seem to go together. If you don’t have his circular path, you can put a handful of pebbl

I agree with Darwin’s combination of rocks, thinking, and walking, they seem to go together. If you don’t have his circular path, you can put a handful of pebbles in your pocket. Then when you’re at a particularly stuck spot in your thinking, toss one away. Works wonders!