In 1784, King Louis XVI asked Benjamin Franklin to investigate an unseen force. A doctor named Franz Mesmer claimed that an invisible magnetic fluid flowed through living bodies, curing ailments whenever he waved an iron wand. Franklin built a blindfold test in a sunny Paris garden.
He touched volunteers with ordinary wooden sticks, pointed the wand in secret, and recorded that people shook with sensation only when they expected the magic to appear.
Franklin never insulted the crowd.
He simply asked the garden for proof.
Today, we face a similarly invisible puzzle directly under our boots. Step onto the damp pine needles. Peer into the moss. Do the birch trees send sugary lunch parcels to their shaded pine neighbors through microscopic fungal threads, or does an entirely different, private trade rule the dirt?
Let us open a theoretical court of inquiry on the forest floor. We seat the mutual-aid society on the defense bench. We seat the solitary merchants on the prosecution side. Both sides bring heavy piles of notebook pages, yet neither side holds a final deed to the truth.
The Case for the Forest Soup Kitchen
Consider the defense. Trees make sugar in their leaves by catching sunlight. Fungi grow tiny, threadlike tubes called mycorrhizae that wrap around tree roots to sip that sweet sap. In return, the fungal threads collect nitrogen and phosphorus from the gravel and deliver those minerals back up into the bark.
The defense argues that this pipeline goes much further. When botanists release specially tagged carbon atoms into the branches of an older spruce tree, those marked atoms travel downward, cross through the fungal net, and surface inside a pale little fir sapling several yards away. Could the older tree play the part of a fond aunt slipping coins into a nephew's pocket?
I adore that image.
It makes the woods look like a cheerful picnic where tall neighbors pass bowls of soup to small sprouts.
Trees share.
Roots unite.
The forest hums like a cooperative bakery.
The Case of the Selfish Mushroom
Now the prosecution stands up, taps a wooden pencil, and objects. Fungi do not run postal services out of charity. A fungus wants lunch.
A single fungal hypha measures only a few microns across, yet that tiny thread demands immense energy to build its walls. What if the fungus merely operates a toll booth? Biologists who re-examine the field trials point out that the volume of transferred sugar stays quite small in natural forest soil. Perhaps the fungus takes the spruce tree's sugar, stores that sugar inside its own subterranean cupboards, and lets a few stray drops leak into the fir root by pure accident.
Can we accuse a mushroom of running an underground grocery store?
We cannot.
Every mushroom cell looks out for its own belly.
The Deliberation
I enjoy arguing with mushrooms. They make stubborn opponents because they never reply. If a Douglas fir loses a cup of carbon to the soil, does the fir mean to help anyone? Trees lack brains, vocal cords, and Sunday manners. Yet living organisms weave clever tapestries without holding committee meetings. Honeybees trace geometric circles without studying math. Creek water finds the ocean without reading maps.
Where does our theoretical jury land? We step out of the courtroom and rest our elbows on a mossy log. The evidence perches in balance. Perhaps the trees genuinely support each other through hard seasons. Perhaps every root and mushroom thread hustles solely for its own dinner, creating the illusion of friendship through thousands of private deals.
Maybe both perspectives capture a slice of the real dance.
I choose not to settle the matter before supper.
The damp dirt keeps its quiet jokes, and the open question feels far more delightful than a tidy verdict.
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