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Agustín Fuentes
Agustín Fuentes, a Professor of Anthropology at Princeton University, focuses on the biosocial, delving into the entanglement of biological systems with the social and cultural lives of humans, our ancestors, and a few of the other animals with whom humanity shares close relations.
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Daniel Dennett
Daniel C. Dennett is the Austin B. Fletcher Professor of Philosophy and director of the Center for Cognitive Studies at Tufts University.Dennett believes it's time to unmask the philosopher's art[…]
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A man with short dark hair in a dark shirt gestures with his hands, pointing with his index fingers, against a plain light background.
Ethan Kross
Ethan Kross is one of the world’s leading experts on controlling the conscious mind. An award-winning professor and bestselling author in the University of Michigan’s top ranked psychology department and[…]
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When we are born, our brains are only about 40% of the size they will reach by adulthood. As we grow, our environments, experiences, and cultures shape both our understanding of the world and the way our brains develop. This is why language is so important: it gives us a tool for growth, thought, and cultural expansion. Daniel Dennett, PhD, Ethan Kross, PhD, and Agustín Fuentes, PhD explain how belief, language, inner chatter, and rituals work together to make us distinctively human.

We created this video for Brain Briefs, a Big Think interview series created in partnership with Unlikely Collaborators. As a creative non-profit organization, they’re on a mission to help people challenge their perceptions and expand their thinking. Often, that growth can start with just a single unlikely question that makes you rethink your convictions and adjust your vantage point. Visit Perception Box to see more in this series.

Humans are particularly distinctive, right? We have these giant brains that develop mostly after we’re born. That allows us to do some things that aren’t seen in other animals. One of those is this incredible human capacity for belief. It’s our ability to take our experiences and imaginations, combine them into ideas or ideologies or perceptions, and commit to them so fully that they become our reality.

One of the problems that has challenged philosophers and cognitive scientists for the last 30 or 40 years is how the brain represents information. An eternally appealing idea is something like a “language of thought.” The brain writes sentences in Mentalese that store beliefs. We have a big library of sentences — those are our beliefs.

But you can’t have an isolated belief. They don’t parcel themselves out the way services do; they come in systems. This is sometimes called holism — a non-holistic theory of belief is a nonstarter.

I think chatter is one of the big problems we face as a species. We spend between one-third and one-half of our waking hours not living in the present. And what do we do during that time? We’re talking to ourselves. Our inner voice is a basic feature of the human mind — it helps us keep verbal information active in our heads. But at other times, it can really sink us.

We can compensate for this feeling of being out of control by creating order around us. Rituals are one way to do that. They give us a sense of order and control that can feel really good when we’re mired in chatter.

When thinking about human evolution, one might wonder: why are humans so complicated? It turns out that, unlike almost all other mammals, our brains at birth are only about 40% of their adult size. This long childhood means that our brains are always in dynamic interaction with other humans, animals, and the environment. Those inputs shape who we are and how we see the world.

We are so complex that things like culture, history, and belief systems enable us to create cultural complexity — ideologies, traditions, and rituals — and make them real for us. That environment becomes part of who we are.

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