How Does The Brain Work?

(I have no idea, and that's ok)

INI logo - default, no tagline


Welcome back.

Over 1600 new readers since last week. Damn.

I had a great, extremely low-key birthday. Thanks to everyone who wrote in, and a massive thanks to my friends for the vegan lasagna, campfire, and gummies. And of course, to the greatest wife who has ever existed for facilitating it all, every day.

Today: How the hell does the brain work? And what does it have to do with lemonade stands and school supplies?

Did you know we record an audio version of all of our essays? Subscribe to our podcast feed and listen to this essay now 👇️ 

I’m Quinn Emmett, and this is science for people who give a shit.

Every week, I help 25,000+ humans understand and unfuck the rapidly changing world around us. It feels great, and we’d love for you to join us.

Together With NomNom

Dogs waiting for bowl of food

Real Food, Real Love. Nom Nom delivers fresh, nutritious meals for thriving dogs.

Experience the difference with Nom Nom's fresh dog food. Made with hearty, real proteins dogs love and packed full of essential nutrients.

Every meal is made just for your dog to help promote a happy, healthy life. Get 50% off your first two weeks (and get free shipping) when you order today.

Want an ad-free experience? Become a Member.

Become a member.

INI is 100% independent and mostly reader-supported.

This newsletter is free, but to support our work, get my popular “Not Important” book, music, and tool recommendations, connect with other Shit Givers, and attend exclusive monthly live events, please consider becoming a paid Member.

How To Give A Shit header

Last week’s most popular Action Step was volunteering for clean, accessible water with Food & Water Watch.

How Does The Brain Work?

If we want to unfuck the future, we’ve got a lot to figure out. But who has to figure it out?

Let’s back up, some context: we’ve already invented most of what we need to build.

And yet — there are some things we do still need to invent. Or at least improve on, or at least understand better, or…at all.

I have shared recently more of the madness behind how I think about how to think about what’s next.

One way I categorize fundamental pieces of the future is like this:

  • What we can’t imagine yet

  • What we already imagined, but don’t know how to build

  • What we already imagined, and we’re building, but it’s technically incredibly difficult and maybe unsafe (?) for whatever reason(s)

  • What we already imagined, already know how to build, but aren’t building (or building enough of) because it’s too expensive or because of political holdups (can be broadly or regionally applicable)

  • What we already imagined, already know how to build, and are currently building

This is basically the funnel through which most ideas and technologies pass, from soap to clean steel to both fission and fusion, cell-cultured meats to mRNA vaccines, solid-state batteries to GPT’s, immunological treatments and CRISPR.

Most of it fails. 

This, despite the best efforts of so many humans working on the frontlines of the future. So many, together, because it turns out innovations happen much differently than we think.

How do new technologies, medicines, etc proceed through that funnel?

It usually starts from basic science research (radioactivity, DNA) and the proceeds, if successful, towards drastically more specific applications for known problems (vaccines, bed nets, solar panels, wastewater epidemiology).

Of course, we simply don’t get the latter without heavily investing in the former, however less sexy and/or profitable basic science may be.

Similarly, research funding varies dramatically across disciplines, usually depending on the addressable market, from cardiovascular drugs to obesity drugs to more rare genetic diseases or kids cancer.

The way we actually go about allocating funding — an endless, distracting grant-making process — is very very annoying, but at least it’s fixable. Human-centered obstacles and bottlenecks are…tougher.

For example, self-driving cars are still really, really difficult, and relatively dangerous, however much progress we’ve made. Meanwhile, human-driving cars are a fucking nightmare, to everyone, for myriad reasons that are much more difficult to solve for.


Imagine for a moment we have all of the money and underlying research technology we need, the best minds thrown at a problem — a necessary problem, one in need of answers, like right meow.

Imagine that with all of this, we still can’t crack it.

Not only can we not crack it, but the best minds seem to agree — broadly — that the more we do find out, the more we’re made aware of how much we don’t know, and further, what we don’t know about what we don’t know.

This is the brain, mostly.

I’m not even talking about brain cancer or CTE. I’m talking about the absolutely herculean efforts required just to understand how it works on a day to day and minute to minute basis, full stop.

Meanwhile, you don’t have to be some bleeding-edge researcher to understand how much we need our brains, to have and love someone affected by some sort of brain injury or disease. It can make the rest of us — standing outside the research but intimately tied to its progress — feel pretty impotent.

We really need to solve for X.

It’s 2023, so surely a supercomputer could help us plumb the depths of gray matter. Here is an example from just this week, courtesy of the Wall Street Journal, of such a device:

“Inside a vast data center on the outskirts of Chicago, the most powerful supercomputer in the world is coming to life. The machine will be able to analyze connections inside the brain and help design batteries that charge faster and last longer.

Called Aurora, the supercomputer’s high-performance capabilities will be matched with the latest advances in artificial intelligence. Together they will be used by scientists researching cancer, nuclear fusion, vaccines, climate change, encryption, cosmology and other complex sciences and technologies.

Aurora is the size of two tennis courts, weighs 600 tons and is expected to be the world’s first supercomputer capable of two quintillion operations a second at peak performance, scientists at Argonne said.”

But there’s a catch. Here’s the first crazy part:

“Researchers recently used Aurora to screen 22 billion drug molecules an hour, accelerating potential drug discovery.”

22 billion drug molecules. An hour. Ok.

Ready for the catch?

“Another potential task is mapping connections in the brain, a task so complicated it could take Aurora a full day to process a tiny sliver of the brain.”

A full day.

To process.

A tiny sliver of the brain.

Yes sure this supercomputer can improve climate change forecasts and maybe also operate its own robots (?) and one of those is great(?)

But let’s come back to the brain.

Here is a very small sliver of the many fundamental things we don’t know about the brain:

  1. How a thought works

Folks, our biggest, baddest supercomputer is Paul-Rudd-in-Wet-Hot-American-Summer-exhausted at the idea of processing even a sliver of the human brain.

About seven years ago (give or take a decade), I had a debilitating months-long streak of what one of the world’s best neuroscientists thought was migraines, but couldn’t be sure.

Couldn’t be sure?

When I asked her what, at least, might be causing these episodes that made it feel like my brain was on an 18th century whaling ship, or how I could possibly relieve them, she — the very best we’ve got, a wonderfully kind, curious, engaged and empathetic human being — shrugged.

Why did she shrug? Consider:

“The number of synapses in one human brain is equal to the number of stars in 5000 Milky Way’s.

And then every synapse has something on the order of 100,000 molecular switches in it.

And these 100,000 switches, protein molecules in every synapse, communicate a lot with one another, they interact a lot.

And then that’s in one synapse, and then the, the human has something between 10 to the 14th, and 10, to the 15th synapses.

Now, okay, so there’s a lot of complexity. And then to make matters worse, it is intricately arranged in very tight quarters.

So the synapse again, there’s a billion of them per microliter of brain volume in a human. remember that each one of those synapses has somewhere between 10 and 100,000, switches in it.”

Then again, AI is here kind of and in some cases might be jumping right past supercomputers:

“Google DeepMind’s AI model, named “GraphCast,” was trained on nearly 40 years of historical data and can make a 10-day forecast at six-hour intervals for locations spread around the globe in less than a minute on a computer the size of a small box.

It takes a traditional model an hour or more on a supercomputer the size of a school bus to accomplish the same feat. GraphCast was about 10% more accurate than the European model on more than 90% of the weather variables evaluated.”

(Vox documented recently why weather apps are seemingly so bad, so this is good news.)

Will we similarly crack the brain? Um, maybe? 

The closest comparison in complexity is probably bacteria and more specifically the gut, which you guessed it, we basically don’t understand, so maybe specifically isn’t the right word here.

Sure, we’ve understood bacteria enough for the last 100 years to discover and save a gazillion lives with antibiotics, but one, we used too much, and two, bacteria outdates us by a lot and will outlive us by just as much. Bacteria will be the last thing standing on this desolate rock as the sun goes red giant, and then white dwarf, consuming everything up to Mars or so.

Not that incredible people aren’t working to understand the whole microbiome and even — considering everything above, this seems outlandish — how the brain and gut connect and interact.

Is it a one way street? Two way street? Are there intersections? Or round-abouts? Is there a street at all? I don’t know, of course. I am an increasingly ancient liberal arts major who lives to ask questions of people a billion times smarter than I am.

What about you?

Understand, though, that we’ve come a long way on most fronts. Even I understand this.

Do you know how long people used to live? Not long.

Do you know how many kids used to die? Most of them! Most!

We didn’t use to wash our hands. We used to dump poop and dead bodies upstream of our drinking water (or at least, somebody else’s) and then not wash our hands after we did it. We used to think storms were acts of some sort of angry god. We thought we were the only planet. Then we thought the sun orbited our planet. Then we thought we were the only solar system, the only galaxy, and so on. Stephen Maturin liberally dosed his seafaring patients with mercury (and himself with opium and cocaine). Bloodletting was a thing, as was astrology and the humors.

In the year of our lord two thousand and twenty three, Cat Bohanon wrote 596 incredible pages describing how the female body actually drove 200 million years of mammalian evolution because we were/are too sexist to have considered that the biologically child-bearing half of our class might be the half that literally made the species what it is today.

And we’ve come a very long way on the brain, too. For example, functional MRI’s are amazing, and we know concussions are a nightmare.

And yet the more we know, the more we know what we don’t know.

Here is a question I have seen in a few places that will screw with you:

“What if the brain can’t understand itself?”

(Also, what is matter made of? And further, how the hell did we evolve from non-living matter? Did viruses start at the same time? Why does time seem to only go forward? How is consciousness? Why are there two different sandwiches called Sloppy Joe’s?)

(Here’s another all-time favorite: What makes you you?)

Enjoy, you’re welcome, good luck.

Here is why I bring all of this up today:

It’s easy to think that unless you are a neuroscientist, a neurosurgeon, a neurologist, a neuropharmacologist, a psychiatrist, someone studying to become one of these, or a gut scientist like my friend Gautam who is linking up with brain people to ask even bigger, harder, more consequential questions, you’re really not going to contribute to meaningful progress on how we understand the brain.

But that would ignore, just to start, how this research is funded.

To say that it takes a village would be a monumental understatement, from program officers to grant managers, to lab techs and grad students, undergrads and support staff.

And it’s this way for most fields.

It’s really, really important we figure out as much as we can about the brain, and how it interacts with the gut, what causes and treats Alzheimer’s, or whatever else. Vitally important.

It’s easy to feel like whatever contribution you can make might not play a significant part in that journey.

I have felt that, I get it, and it’s wrong.

Sure, self-awareness is key and it’s the real reason we all constantly ask the question, “How can I help?”

Not just because we are Shit Givers at heart, but because we already know our limitations, and they can make us feel pretty goddamn impotent when the shit hits the fan.

If you are someone who is interested and capable of becoming a scientist, doctor, or elected official, go do it. That’s incredible. I’m here for it.

But I’m certainly not one of those people.

When my grandparents had dementia, when my cousin and late friend had cancer, when my cousin and uncle had A.L.S., when everyone was stuck at home because of COVID, and a million other days, I, too, stewed in my thoughts and emotions, asking over and over “What the fuck can I actually do about any of this?”

The best answer is, of course, “What CAN you do?”

Because you can always show up. There are always action steps.

You can always raise money for care; you can volunteer for a clinical trial; you can (almost) always give blood. You can always run a race with or host a lemonade stand for a reputable organization who is raising money for pediatric cancer research.

You can recruit, campaign for, and get elected candidates who have had brain cancer or abortions, who have suffered from a lack of health insurance, or who were emergency room doctors, or all of the above.

You can always buy air purifiers for local classrooms (leaning on research that’s already be done), even if you don’t have kids.

You can always yell at your city council to subsidize induction stoves for low income renters, to remove the lead from your pipes, to build bike infrastructure and charge out the ass for parking, and to apply for that fresh federal electric school bus money.

If you’ve got the cash, you can get a Mill bin and then invite your friends over for what they think is a dinner party but is actually like one of those old-timey Tupperware parties where you are mostly extolling the many virtues and co-benefits of reducing food waste.

You can get solar and advocate for a gas ban; you can interrogate your company’s mission statement, product lines, and supply chains, even if you are a “solopreneur”; if you know your way around a hammer you can help build affordable housing; you can contribute to disaster relief around the world; you can play your flute or other instrument at a dementia care community; you can bring your golden retriever or rescue whatever to say hi to sick kids.

There is so much you can do.

I, too, dream of a radically cooler future filled with widely-available technologies we can’t even begin to dream of. 

But most impactful work we can do to get there is often the most basic and pragmatic, attacking today’s known weaknesses and opportunities to raise the baseline, to make sure everyone has bootstraps, to make sure scientists and inventors and ethicists on the frontlines of the future don’t spend all of their time writing grant proposals, to make sure teachers aren’t paying for their own classroom supplies.

If you don’t have a lot to give but you do really want to give, giving a tax-exempt church or a progressive senate candidate in a die-hard red state (or die-hard blue state) your hard-earned cash is going to go way less far than donating to a local school board race, buying a single bed net, or giving it to a specific teacher through DonorsChoose. It’s just math.

We can do all of these things at once, and none of us has to do it alone. Don’t worry, I’m not going to tell you there as many of us as there are synapses in the brain — I’m not that bad at math. But as Dr. Tobias Fünke once put it — there are dozens of us. Dozens!

We can dream of a wildly imaginative future at night and and spend our days laying the bricks for a real one that our kids and other people’s kids and their kids will actually experience. Where every brick matters.

Wouldn’t that be nice? To live to see the fruit of our efforts? So maybe the youths won’t be quite so mad at us?

You can always show up, you can always take action, you can always use your unknowable brain and perfectly-understandable heart to move the needle to do better better.

🙋‍♀️ Today’s Poll

Last week, 31% of you said that “inequality” was your favorite co-benefit (again, “favorite” probably isn’t the right word here, but you get the point).

How important is it to you that we include and expand Action Steps outside of the US?

Login or Subscribe to participate in polls.

Want to talk climate strategy, investing, or anything else?

Want to sponsor the newsletter?

Get your brand, product, or service in front of 25,000+ sustainably-minded consumers:

Join the conversation

or to participate.