Erika Price’s article about the soul, “Soul Searching,” intrigued me.  I’ve always assumed that people believed in the soul because they were terrified at the thought of being permanently deprived of the companionship of those they love.

I think, though, that there is a often-unnoticed prerequisite to believing in souls.  One first needs to make an intellectual move that is so commonplace and subtle that it is easily missed.  This early profound move, that of presuming that the soul is a thing, is a critical move with profound ramifications.

Subtle early changes often play out profoundly in the long run.  Consider, for instance, the sensitive dependence on initial conditions within chaotic systems popularly known as the butterfly effect. Small variations of the initial condition of a dynamical system may produce large variations in the long-term behavior of the system. 

Here’s another example of a subtle early adjustment paying off in a big way.  In 1970, when it was still 321,860 km from earth, the Apollo 13 spacecraft was damaged by an explosion, causing the Service Module to lose its oxygen and electrical power.  The astronauts were required to carefully fire the engines briefly and manually to correct their course to achieve a re-entry angle of 6.49 degrees. That short burst of the engine thus effected a tiny course correction that was a matter of life and death by the time Apollo 13 hit Earth’s atmosphere. 

We also make subtle language moves that eventually make huge differences in …