Children are the key to solving a 2000 year old philosophical mystery

Developmental psychologist Alison Gopnik has published countless studies in prestigious journals. Her work covers how children are more open-minded than adults (and often learn better, as a result), and how they approach the world (in much the same way as scientists). Each finding is significant on its own but, collectively, says Gopnik, she’s working towards solving “the biggest, deepest question in philosophy.” 

That question is, essentially, how do we have knowledge about what surrounds us? To a layperson, the answer may seem obvious: We have senses to see, hear, and touch. But our senses provide limited, imperfect information. We assume that what we see is an accurate reflection of reality, because we’re only able to witness the world through our own eyes. But this simply means that we’re limited by our own visions.

We also have “abstract knowledge,” an understanding of concepts that aren’t dependent on physical objects, like the number “five.” We can point to five pencils and add them up, but we don’t need to refer to five concrete objects to understand the concept of “five.” Other abstract objects include shapes, the essence of colors, and amorphous ideas like justice and humanity. Stanford Encyclopedia lists a few more: “goodness, beauty, equality, bigness, likeness, unity, being, sameness, difference, change, and changelessness.”

“All that reaches us from the world are a bunch of photons hitting our retinas,” says Gopnik. “How to we turn this confused, insufficient mess of information into concrete, meaningful objects?” How are we able to make so much sense of the limited information that comes to us through our senses? Philosophers have attempted to tackle this problem for more than 2,000 years, beginning with Plato and Aristotle.  

Broadly speaking, Plato argued that we have knowledge of these abstract objects, independent of sensory experience. (So, we know that there have five pencils because we have an abstract understanding of the concept of “five.”) Meanwhile, Aristotle argued that we aren’t born with such knowledge at all, and that all our knowledge comes from experience. (So, in his view, we only seem to have abstract knowledge of “five” after seeing enough examples of five concrete objects.) “Those two—top-down versus bottom-up, nativist versus empiricist—approaches to answering that question have just echoed down through the ages,” adds Gopnik.

Instead of focusing on how adults understand the world, Gopnik believes the answer lies with how children seem to learn about the world. In many ways, she says, it seems they’re born with a huge amount of knowledge. And yet, of course, they’re also making mistakes, and figure things out from sensory experiences. “It doesn’t look like what children are doing is just putting details into a hypothesis they knew all along. It looks as if they’re really learning about the world,” she says. “But it also looks as if they have abstract knowledge about the world essentially from the time they’re born, or at least from the time they’re very young babies.”

Her studies have given credence to her instincts, showing that babies know a lot early on (for example, by 18 months, babies can understand that we don’t all want the same things), but also that they seem to change what they think based on experience. Gopnik’s studies have given weight to “theory theory,” which essentially argues that children learn about the world just as scientists make new discoveries: By developing hypotheses and adjusting them based on new experiences.

That leaves the question, though, of how children develop these hypotheses in the first place. Gopnik’s believes our exceptionally long periods of childhood, with its limited responsibilities, is key to how humans develop and experiment with new ideas.

There’s a tension, she says, in adult life between testing radical (if exciting) changes to behavior in search of a brilliant solution, and trying a more risk-adverse (if safer) approach of incremental change. Childhood is a time where we can explore all manner of hypotheses without bearing the full weight of decision-making; adults are watching over us to make sure things don’t go too wrong. “The very fact of childhood is one of the ways we resolve that tension between Plato and Aristotle’s theories,” says Gopnik.

This suggests that children are born with some basic abstract knowledge and rely on experience to test a huge number of theories and build up knowledge of other abstract concepts (though, of course, the question of precisely which abstract concepts form the basis of the initial hypotheses that children test is still unknown.)

The question of how knowledge is formed informs artificial intelligence, as well. Gopnik notes that computer scientists from Google’s DeepMind and Uber’s AI team have spoken to her and other development psychologists to see if the two fields can collaborate, and whether computers can learn by mimicking the models that children use.  

If we want to create machines with human-like intelligence, Gopnik says computers will have to be programmed to think like children. The importance of children to AI was also noted Alan Turing’s famous 1950 paper on machine intelligence. “Instead of trying to produce a program to simulate the adult mind, why not rather try to produce one which simulates the child’s?” he writes.  

“No one ever talks about this,”Gopnik adds.

Gopnik is used to the importance of children being dismissed. “Anyone who does developmental psychology, especially if you’re a woman, has experienced the reaction, ‘You’re doing the same thing as a preschool teacher,’” she says. In the New York Times review of her book, The Philosophical Baby, the reviewer suggests “perhaps children have been left out [of philosophy] simply because they are on the whole not all that relevant.”  

Or, as Gopnik argues,  it could be that “philosophers have been almost uniformly male and mostly celibate.” 

Gopnik began her career in philosophy before transitioning to development psychology, and says she can never be truly sure that she didn’t leave philosophy because it was so dismissive of both children and women. 

“Maybe what you should do is take all these things that have traditionally been treated with some contempt because they’re associated with women, like emotion or childhood,” she says. “And say these things are actually just as serious and can tell us just as much about the human condition.”