It sounds like it is about the left and right hemispheres of the brain. There is a poem he wrote about it as well:

"The Mycologist & The Mathematician

This is the story of prodigal friends
A complex encounter which starts where it ends
A labyrinth of thinking, all ladders and snakes
One sleeps every move, while the other awakes
One of these men had a maze in his mind
The other connected to all things outside
Their energy flows in the tricks that they play
Each of them experts in opposite ways
First the mycologist, mushrooms and mould
He reads his opponent, then looks to his soul
Then Mathematician, equations sublime
Puzzling his foe as he travels through time
Organic in nature, they journey so far
Seeking their clues in the dust of the stars
Unlocking all secrets and cosmic laws
Solving all riddles, unlocking all doors"