the details are never the same. Everything evolves. Innovation is requisite. Humans require novelty.
So there’s a balancing act here. On the one hand, brains try to save energy by predicting away the world; on the other hand, they seek the intoxication of surprise. We don’t want to live in an infinite loop, but we also don’t want to be surprised all the time. You don’t want to wake up tomorrow to find it’s Groundhog Day again, and you also don’t want to awaken to discover that gravity has reversed and you’re stuck against the ceiling. There’s a trade-off between exploiting what we know, and exploring the unknown.
THE BALANCING ACT
Brains seek a balance between exploiting previously-learned knowledge and exploring new possibilities. This is always a tricky trade-off.4 Say you’re deciding which restaurant to go to for lunch. Do you stick with your traditional favorite or try something new? If you go for your familiar haunt, you’re exploiting knowledge you’ve gained from past experience. If you jump into the culinary abyss, you’re exploring untried options.
Across the animal kingdom, creatures set their trade-off point somewhere in the middle. If you learn through experience that the red rocks have grubs under them while the blue rocks do not, you need to exploit that knowledge. But one day you may find that grubs aren’t there, whether because of drought, fires or other foraging animals. The rules of the world rarely hold constant, and this is why animals need to take what they’ve learned (the red rocks yield grubs) and balance that against attempting new discoveries (I wonder what’s under these blue rocks?). And this is why an animal will spend most of its time looking under the red rocks, but not all of it. It’ll spend some time looking under the blue rocks, even if it has looked there several times in the past, unsuccessfully. It’ll continue to explore. It’ll also spend some time looking under the yellow rocks and in tree trunks and in the river, because one never knows where the next meal is going to come from. Across the animal kingdom, hard-won knowledge is counterbalanced with new pursuits.
In the course of developing over eons, brains have achieved an exploration/exploitation trade-off that strikes the balance between flexibility and rigor. We want the world to be predictable, but not too predictable, which is why hairstyles don’t reach an endpoint, nor do bicycles, stadiums, fonts, literature, fashion, movies, kitchens, or cars. Our creations may look largely like what’s come before, but they morph. Too much predictability and we tune out; too much surprise and we become disoriented. As we’ll see in the coming chapters, creativity lives in that tension.
The exploration/exploitation tradeoff also explains why our world is so densely populated with skeuomorphs: features that imitate the design of what has come before. Consider that when the iPad was introduced it featured a “wooden” bookshelf with “books” on it – and the programmers went to great lengths to make the “pages” turn when you swiped your finger. Why not simply redefine a book for the digital era? Because that’s not what made customers comfortable; they required a connection to what had come before.
Even as we move from one technology to the next, we establish ties with the old, marking a clear path from what was to what is. On the Apple Watch, the “Digital Crown” looks like the knob used to move the hands and wind the springs on an analog timepiece. In an interview with the New Yorker, designer Jonathan Ive said that he placed the knob slightly off-center to make it “strangely familiar.” If he had centered it, users would have expected it to perform its original function; had he removed it, the watch wouldn’t have looked enough like a watch.5 Skeuomorphs temper the new with the familiar.
Our smartphones are packed with skeuomorphs. To place a call, we touch an icon of an old phone handset with an extruded earpiece and mouthpiece – a profile that departed the technology landscape long ago. The camera on your smartphone plays an audio file of a shutter sound, even though digital cameras don’t have mechanical shutters. We delete the zeros and ones of our apps by dragging them to the “trash can.” We save files by clicking on the image of a floppy disk – an artifact that has gone the way of the mastodon. We purchase items online by dropping them into a “shopping cart.” Such ties create a smooth transition from the past to the present. Even our most modern tech is tethered with an umbilical cord to its history.
The exploration/exploitation trade-off is not unique to humans, but while generations of squirrels have poked around in different bushes, humans have taken over the planet with their technology. So there’s something very special about the human brain. What is it?
WHY ZOMBIES DON’T DO WEDDINGS AND BAR MITZVAHS
If you sat down for dinner with a zombie, you would not expect to be impressed with a creative idea. Their behaviors are automatized: they are only running pre-configured routines. That’s why zombies don’t skateboard, write memoirs, launch ships to the moon, or change their hairstyles.
Make-believe though they are, zombies show us something important about the natural world: creatures throughout the animal kingdom run mostly on automated behavior. Consider a honeybee. A stimulus leads to the same reaction, every time, enabling the bee to negotiate such options as land on blue flower, land on yellow flower, attack, fly away. But why doesn’t a bee think creatively? Because its neurons are fixed into place and pass signals from input to output like firefighters passing water pails in a bucket brigade.6 In the bee’s brain these brigades begin to form before birth: chemical signals determine the routes of the neurons, and thus build the different brain regions associated with movement, hearing, vision, smell, and so on. Even when it is exploring new territory, the bee is operating largely on auto-pilot. You can’t reason with a bee any more than you can with a zombie: it is a biological machine, with its thinking hard-wired by millions of years of evolution.
We have quite a bit of the bee in us: the same sort of neural machinery allows us to have our massive portfolio of instinctual behaviors, from walking to chewing to ducking to digesting. And even as we learn new skills, we tend to streamline them into habits rapidly. When we learn how to ride a bicycle, drive a car, use a spoon, or type on a keyboard, we burn the task into fast pathways in the neural circuitry.7 The most rapid conduit becomes favored over other solutions, minimizing the brain’s chance of making an error. Neurons that are not required for that task are no longer triggered.
If the story ended there, the human ecosystem as we know it wouldn’t exist: we wouldn’t have sonnets, helicopters, pogo sticks, jazz, taco stands, flags, kaleidoscopes, confetti, or mixed drinks. So what’s the difference between a bee brain and ours? While a bee brain has one million neurons, a human one has one hundred billion, giving us a larger repertoire of behaviors. And we’re privileged in another way, too: not only in the quantity, but the organization of those neurons. Specifically, we have more brain cells between sensation (what’s out there?) and action (this is what I’m going to do). This allows us to take in a situation, chew on it, think through alternatives, and (if necessary) take action. The majority of our lives take place in the neural neighborhoods between sensing and doing. This is what allows us to move from the reflexive to the inventive.
The massive expansion of the human cortex unhooked huge swaths of neurons from early chemical signals – hence these areas could form more flexible connections. Having so many “uncommitted” neurons gives humans a mental agility other species don’t have. It makes us capable of mediated behaviors.
Mediated (as opposed to automated) behaviors involve thought and foresight: understanding a poem, navigating a difficult conversation with a friend, generating a new
