Frank Noir

“Here’s how I’ve always pictured mitigated free will:
There’s the brain—neurons, synapses, neurotransmitters, receptors, brainspecific transcription factors, epigenetic effects, gene transpositions during neurogenesis. Aspects of brain function can be influenced by someone’s prenatal environment, genes, and hormones, whether their parents were authoritative or their culture egalitarian, whether they witnessed violence in childhood, when they had breakfast. It’s the whole shebang, all of this book.
And then, separate from that, in a concrete bunker tucked away in the brain, sits a little man (or woman, or agendered individual), a homunculus at a control panel. The homunculus is made of a mixture of nanochips, old vacuum tubes, crinkly ancient parchment, stalactites of your mother’s admonishing voice, streaks of brimstone, rivets made out of gumption. In other words, not squishy biological brain yuck. And the homunculus sits there controlling behavior. There are some things outside its purview—seizures blow the homunculus’s fuses, requiring it to reboot the system and check for damaged files. Same with alcohol, Alzheimer’s disease, a severed spinal cord, hypoglycemic shock. There are domains where the homunculus and that brain biology stuff have worked out a détente—for example, biology is usually automatically regulating your respiration, unless you must take a deep breath before singing an aria, in which case the homunculus briefly overrides the automatic pilot.
But other than that, the homunculus makes decisions. Sure, it takes careful note of all the inputs and information from the brain, checks your hormone levels, skims the neurobiology journals, takes it all under advisement, and then, after reflecting and deliberating, decides what you do. A homunculus in your brain, but not of it, operating independently of the material rules of the universe that constitute modern science.
That’s what mitigated free will is about. I see incredibly smart people recoil from this and attempt to argue against the extremity of this picture rather than accept its basic validity: “You’re setting up a straw homunculus, suggesting that I think that other than the likes of seizures or brain injuries, we are making all our decisions freely. No, no, my free will is much softer and lurks around the edges of biology, like when I freely decide which socks to wear.” But the frequency or significance with which free will exerts itself doesn’t matter. Even if 99.99 percent of your actions are biologically determined (in the broadest sense of this book), and it is only once a decade that you claim to have chosen out of “free will” to floss your teeth from left to right instead of the reverse, you’ve tacitly invoked a homunculus operating outside the rules of science.
This is how most people accommodate the supposed coexistence of free will and biological influences on behavior. For them, nearly all discussions come down to figuring what our putative homunculus should and shouldn’t be expected to be capable of.”
― Robert M. Sapolsky, Behave: The Biology of Humans at Our Best and Worst