Perception gets constructed, deconstructed, and reconstructed as the body evolves in relationship to its environment. It can update itself based on reconciling prediction errors, or it can project itself into the world through action.

Part 2 models at how the different elements of experience might interact within the predictive theory. Its point is not to perfectly capture real-world complexity, but step outside of the system and actually see its mechanics at work. It's high-level awareness that reveals leverage points, so we can be intentional with our experience and behaviour.

Let’s consider three things we might want to improve with intention:‍

• Relationship to the self
• Relationship to others
• Relationship to goal-oriented work

Relationship to others

To improve the relationship to others, focus on speech and behaviour.

People don't perceive your beliefs or intentions, only the output: what you do and say. Help them understand you better by choosing words and actions carefully. You can iterate this through awareness of the impact your words and actions have with others and how your intentions may be misinterpreted.

Empathy

Through the lens of the predictive model, empathy is the brain inferring how someone else is feeling. It does this by anticipating and interpreting sense data (i.e. actions and words they see and hear) through the concepts it modelled from past experiences and what it learned from others, books, movies, and so on.

Overcoming experiential blindness

So, not only do people not see your beliefs or intentions, they are also likely to see your words and actions differently than you do, from their different internal models.‍

"If you'd understood everything I said, you'd be me." — Miles Davis

If two people don't have concepts to interpret certain sense data in terms of feelings, they might not "see" them at all, i.e. they are experientially blind to it.

The more different two people are, the harder it is for their brains to infer how the other is feeling — the harder it is to empathise with each other.

For example, on a Lex Fridman podcast, neuroscientist Lisa Feldman Barrett suggests children of colour in the United States are under-prescribed medicine by physicians not necessarily because they're racist, but rather because they are experientially blind to what they're feeling. Similarly, female patients are often misunderstood by male doctors — sometimes dangerously so. Different lives create different concepts construct different experiences.

"A person hears only what they understand." — Johann Wolfgang Von Goethe

Thoughtfully expressing outwardly how you feel makes it easier for others to empathise with you. It signals other brains sense information to sample and infer your feelings from, through their own conceptual maps.

Empathy is felt because your brain is literally constructing emotions: you feel as your brain understands how the other feels, from its own emotional concepts.

Syncing brains through prediction errors

Since no two people are identical, one can ever only approximate what the other is feeling in their own way.

Open dialogue can bridge the gap, syncing each other's concepts through reflexive feedback. This requires genuine motivation from both sides, to understand and be understood. Better yet, to have one’s concepts understood, one also needs to other understand the other’s concepts so to be able to communicate one’s own concepts in terms the other understands. Effective empathy is a two-way street wherein brains meet each other halfway. In the process, concepts on both sides assimilate.

Obvious as that may sound, remember concepts only update through prediction errors; something the brain by default prefers to avoid because of the metabolic tax. In fact, people often unintentionally mistake learning someone else's concepts (empathy) for trying to validate their own. Rather than trying to see the other, they themselves try to be seen. ‍

Empathy only works when you care enough to pay the metabolic price of learning the other; to actively seek out where your concepts fall short to construct how the other feels (prediction errors) in open dialogue — enriching them in the process.

The best/worst thing for a brain is another brain

Why bother with empathy in the first place if it costs metabolically?

Your brain's job is to anticipate and meet your body's needs so you are at all times ready to act as you need to. It continuously makes predictions when to deposit, withdraw or invest bodily resources given the situation, e.g. can we relax, rest and replenish (deposit), should we release cortisol to ready the body for action (withdraw) or is it a good time to work out so the body grows stronger (invest)?

The metabolic roots of depression and anxiety

Your actions can only be as effective as your predictions. In novel and chaotic situations, your brain is forced to learn and pay a higher metabolic price. You may start to feel distressed and overwhelmed, typically a signal to withdraw to safe place like home where everything is predictable so you can rest and replenish.

‍But when unpredictability costs for too long, predictions become chronically mismatched, actions ineffective and body budgets mismanaged. Exhausted metabolic resources in turn impair the brain's predictive ability in a vicious cycle; less and less can it afford to learn from prediction errors and thus keeps repeating them. As distress and misguided predictions feed each other, unpredictability becomes ubiquitous to the point where you struggle to relax and replenish even at home.

Lisa Feldman Barrett proposes such a downward spiral of stress, metabolic depletion, misguided energy regulation and ineffective predictions as a way to think about depression and anxiety.

A hug a day keeps metabolic imbalance at bay

Framing depression as metabolic illness highlights the importance of of sleep, healthy eating and exercise. Where does empathy come in?

Your brain can rely on other brains to help manage its body budgets. Humans evolved to take care of each other's nervous systems. Empathy originates from caretakers guiding baby brains through the sensational sea of uncertainty. While parents take care of their children’s body budgets (feeding and protection), they also guide them how to map, feel and act in certain contexts and situations — shaping first predictions so they themselves learn to manage their bodies.

Even so we grow up to take care of ourselves, the people close to us still help relieve stress in much the same way. With empathetic words and actions (hugs), they help us make sense of uncertain situations — instilling us with confidence to resolve doubts (thought) through action. Knowing you’re not alone makes you feel safer and stronger. As such, the empathy of others lightens the metabolic load and co-manages your body budgets.‍

Think about the impact of a hug or even a simple WhatsApp message from a loved one has on how you feel — it regulates your nervous system. When your partner texts I love you, it changes your heart rate, breathing and metabolism. You feel this as affect, and conceptualise it as emotion. Same effect in the opposite sense when the message adds to uncertainty and is felt as anxiety, e.g. You are useless.

In that sense, the best thing for a human brain is another brain. Inversely, other people can also majorly add to the chaos and uncertainty in our lives. And so, unfortunately, the worse thing for a human brain is also another brain.

You are your relations

It’s easy to see why we evolved as social animals. For most of history, survival and thrival odds were higher for individuals in groups. Empathy scaled from kin to tribe to community levels alongside the success of big groups working together. Nowadays most societies collectively solved food, shelter and security needs to the extent you can easily survive on your own. Yet, empathy still has clear biological advantages.

You can perfectly manage your nervous system on your own, but it'll metabolically cost you more. Dealing with life's inherent uncertainty all by yourself takes a slow but certain toll over time. So much so you’re likely to die sooner.

‍Many studies have replicated a negative causal link between loneliness and longevity. On average, people who are socially isolated, living alone or experiencing loneliness are ~50% (adjusted for age and gender) more likely to die earlier than people with close relationships — friends, lovers, and even pets. Along the same lines, the widowhood effect is the increased possibility of a person dying shortly after a long-time partner's passing. Losing the main steward of your nervous system devastates metabolic health, making you more vulnerable to disease. People literally die from a broken heart.

Losing a loved one is often described as losing a part of your self. That’s because, in fact, you have lost a part of your self. That someone co-managed your body budgets and was an inherent part of the concepts that make up your sense of self.

“Tell your friend that in his death, a part of you dies and goes with him. Wherever he goes, you also go. He will not be alone.” — Jiddu Krishnamurti

‍Biologically, empathy is a metabolic investment: it costs short-term but pays long-term.

• In intimate terms, it builds a close circle of people that help manage your body budgets by reducing fundamental uncertainty in many ways.
• On a larger scale, the bigger the diversity of people you invest to empathise with, the richer your concepts, the more of reality you know to navigate, the less uncertainty your brain has to deal with altogether.

Empathy works like a flywheel, too: the more people you empathise with, the easier it becomes (the lower the metabolic cost) to empathise with the next one. You grow in complexity in a dynamic, integrative way and are healthier off because of it. Though beware of empathising with others who don't empathise with you. Helping manage others' body budgets while no one helps with yours only adds stress.