Reality is neither purely out there nor purely inside your head, according to psychologist Lisa Feldman Barrett, a University Distinguished Professor of Psychology at Northeastern University in Boston. In a short Big Think video, she lays out what she calls relational realism: every moment you live through is assembled in real time from the sensory signals reaching your body and the remembered past your brain uses to interpret them. That remembered past, which she also calls your perception box, is the lens through which each moment arrives. Because every observer carries a different box, reality exists in relation to the person experiencing it, and in relation to everyone sharing the moment with them. The ideas reach from the old philosophical riddle about a falling tree to the ordinary arguments people have at dinner, and Barrett ends on a prescription that has less to do with winning than with staying curious.
The scene she starts with is one most people will recognize. Two people sit in a therapist's office. One says, with feeling, that they are really, really mad. The therapist looks back and says, no, actually, you're really sad. Who is right?
Barrett acknowledges the traditional answer. Since humans began talking to one another, she notes, people have assumed an objective reality exists out there, separate from us, and that we perceive it with more or less accuracy. In that framework, the therapist's office has a single correct answer, and one of the two speakers, or both, has missed it.
Barrett rejects both camps. "Reality is not purely objective and it's not purely subjective," she says in the video. "It is relational. There is one reality that is perspective dependent. I experience anger. My therapist is experiencing me as sad. And together, that's the reality of the situation." (Roughly 0:52 into the video.) The anger is real. The sadness the therapist perceives is also real. Neither is a distortion of a hidden fact; both are parts of one situation that exists only with both perspectives in it.
She is also skeptical that the philosophical argument has been framed well. Philosophers, she says, have debated whether reality is out there or in your head for millennia, and she thinks they are "probably asking the wrong question." Her alternative starts from what the brain actually does.
Barrett's core claim is that everything you do and everything you experience is a combination of two things: the remembered past and the sensory present. The sensory present is the raw input: the signals hitting the retina in each eye, the cochlea in each ear, the receptors in the skin. The remembered past is the stored experience your brain uses to anticipate what those signals mean.
She treats reality as "made up of stable patterns of signals," and she points to the best available evidence that the brain uses past experience to anticipate incoming sensory signals from the world. Under that model, reality is not simply delivered to you. It is predicted, checked against input, and built. That is why the outside world and your interior are not two separate territories. The line between them runs through your own sensory surfaces and your own history.
The perception box is her name for the remembered past in this role. Her phrasing is precise: the box is "the ingredients, the signals that you bring to creating the relational present." Two people walk into the same room with different boxes, and so they build slightly different presents out of identical furniture, voices and light.
The old parable asks whether a tree that falls in an empty forest makes a sound. Barrett's answer is a conditional no. A falling tree does set vibrations moving through the air, and a relational realist would say that a set of receptors is needed to detect those vibrations. Yet detection alone is not enough. "In order for it to be a sound of a tree falling, an organism has to know that that's what those sounds mean." (Around 3:18.)
Put plainly: the vibrations are physical, but the sound of a falling tree is a relation. It requires a sensing body, and it requires a brain carrying the meaning that makes a particular pattern of vibration into "tree falling." Remove the organism and the physical event still happens, but the sound, as an experienced reality, does not. The same logic changes the answer for other creatures. Their sensory surfaces are different, so the reality they inhabit is different too.
Barrett's example is the ocean. There is a great deal of vibration-based noise in the water that humans do not detect and that is not especially relevant to us. Whales do detect those signals. For them, those signals, produced by their own sensory surfaces and brains, are part of reality from their perspective.
The point is not just a curiosity about marine biology. It is a warning about human ignorance. "We interfere with their ability to communicate with each other by our ignorance of their perspective," she says. In other words, an environment is not neutral. When people act as if their own sensory range defines what is real, they can disrupt other creatures' realities without ever noticing. The same blindness, she suggests, applies between people.
This is where the theory becomes personal. In an argument, people often reach for the authority of objective reality: I am right because that is simply how things are. If reality is relational, that move is no longer available. Barrett's conclusion is direct. To resolve the conflict, you must accept that someone else's experience has equivalent authority to your own.
She is careful to add that this does not erase your experience. "The idea that somebody else's experience is part of reality as much as yours doesn't invalidate your experience," she says. "It means that your experience is a part of reality, but it's not the only part." There are parts of reality that the two people share, and other parts that each of them alone can access. The therapist's office holds both the anger and the sadness, and neither speaker has the whole picture by themselves.
This reframing shifts the goal of an argument. It is no longer about prevailing over a fact that stands outside both parties. It is about assembling a larger account of the shared situation, which requires each person to admit that their own box is only one of the boxes in play.
Barrett's most practical point concerns the company we keep. If you spend time with people who are just like you, who share your reactions and your experiences, you reinforce the remembered past that is easiest for you to conjure. Your box becomes smaller and more predictable, and reality shrinks to match it.
The alternative is curiosity. "If you are curious, if you're foraging for new sets of signals, new meanings, you are very likely to expand the aspects of reality that you have access to," she says. The word "foraging" matters. It frames curiosity as an active search for inputs and interpretations you do not already own, not a passive openness you wait around to feel.
She pairs curiosity with humility, and she ties both to an ethical stance. "The goal there is to be curious and be humble. As a person, I think it's incumbent upon us ... we really ought to experience as many aspects of reality as we can. Otherwise, we're ignorant, and ignorance is not helpful." (Near the close of the video.) Her final line draws the distinction sharply: ignorance, she says, "has nothing to do with objectivity. It has everything to do with being able to experience as much of reality as possible."
That final sentence is the piece's real takeaway. Barrett is not telling viewers that nothing is true. She is telling them that truth, as far as people can reach it, is something built jointly from many boxes, and that the widest reality is available to those willing to look through someone else's.
Start with the therapist's office. The next time you are certain someone else has misread a situation, ask what signals they are working from and what remembered past shapes their reading. Then ask what your own box might be leaving out. That is the practical move Barrett describes: treat the disagreement as a clue to a larger reality rather than a verdict to be won.
For the full context, Big Think's Perception Box series hub and the complete interview with Barrett, both on bigthink.com, extend the argument beyond this short clip. Read Barrett's own words in the source video before drawing conclusions, and let her framework be a tool for curiosity rather than a new authority to hide behind.
