Both lost their mothers in early childhood. Both suffered from depression... and both wrestled with religious doubt. Each had a strained relationship with his father, and each of them lost children to early death...
- They were both Aquarians.
- They both had beards.
- Their first names each contain seven letters.
- While Lincoln was President of the United States, Darwin was Secretary of the Geological Society.
- They were both fond of pigeons (tentative conclusion).
- They are both reviled in Mississippi.
— Larry, Attack Monkey, Light Reading