What is the meaning of life?

▶ It’s a profound, poetic, and timeless question.^[1] But before we can explore its meaning, we must first ask: what is life? Definitions are still debated, especially when considering artificial life, synthetic biology, or non-Earth-based life forms, which may not fit standard criteria. Here, I frame the discussion from a scientific (especially Western) perspective, but many religious, non-Western, and Indigenous worldviews offer alternative understandings of life, agency, and meaning.^[2]

Life¶

In biology, life is commonly defined as possessing several essential characteristics, including organization, metabolism, homeostasis, growth, adaptation, response to stimuli, and reproduction. While many biological entities display these traits, some exceptions exist; for example, viruses challenge traditional definitions because they lack metabolism and only reproduce within hosts.

NASA aims to define life without being too narrow (e.g., carbon-based life only) or too broad (e.g., labeling everything alive). It uses the concept of a self-sustaining chemical system capable of Darwinian evolution, focusing on life’s ability to maintain itself, evolve, and inherit and transform genetic information.

From a thermodynamic perspective, life is a non-equilibrium system^[3] that uses energy gradients (like food or sunlight) to maintain internal order by resisting entropy (disorder).^[4] However, due to the second law of thermodynamics,^[5] this local order comes at the cost of increasing entropy in the surroundings. Think of life like a campfire: it stays burning by consuming wood (energy) and releasing heat and smoke, maintaining structure while spreading disorder outward. Also note that nonliving things like rocks also move irreversibly toward higher entropy with no internal energy processing or resistance.

By integrating insights from biology and thermodynamics, some scientists frame life statistically using concepts from thermodynamics, Bayesian inference,^[6] and information theory. In this view, a living system that survives or self-sustains acts as a probabilistic model, predicting sensory inputs and continually minimizing the expected surprise (the statistical improbability of its observations). Since calculating true surprise is impossible, the system instead minimizes variational free energy, a mathematical tool that serves as an accessible stand-in for surprise. Variational free energy can be thought of as a measure of how well a system’s internal model explains its experiences: the lower the free energy, the fewer the surprises.^[7] For example, a bacterium that predicts where food will appear updates its internal model to minimize surprise and thus conserve free energy. This process maintains its inner workings in order. Biological systems achieve this through perception, learning, and action, which require energy and produce waste heat; thus, in maintaining order through perception, learning, and action, they increase entropy in the environment. Life doesn’t eliminate entropy; it redistributes it.

While Bayesian/statistical frameworks are influential and offer valuable insights, they are not the only perspectives for understanding life. Other approaches emphasize chemistry, systems theory, phenomenology, or alternative models, and some philosophers argue that “life” is a cluster concept, meaning that no single set of criteria suffices for every context, and definitions shift as knowledge and technologies evolve. Additionally, as artificial intelligence and synthetic systems become increasingly complex, some argue that certain artificial systems may meet key criteria for life, such as self-organization, learning, adaptation, and maintaining boundaries. This is an ongoing scientific and philosophical debate, with significant ethical implications, including questions about sentience, rights, and the responsibilities humans hold toward artificial or digital forms of life.

Life keeps itself going by staying organized inside while releasing mess (entropy) outside. It learns from the world to avoid surprises and uses its genes to pass down the legacy of what it has learned. A living system (life) is an autonomous agent that uses energy to preserve its structure, update its internal model through learning, and encode this information in replicable formats (like DNA), ensuring continuity through heritable variation.^[8]

All living systems share these core traits, such as metabolism, energy use, learning, and information transfer, but they differ in degree across key dimensions. Autonomy reflects a system’s ability to maintain internal boundaries that shield it from external disturbances. Inference capacity refers to a system’s ability to model and predict its environment with depth and accuracy. Legacy modality encompasses the complexity of how information is passed on, ranging from genetic to cultural forms. Not all cultures or species value legacy in the same way; access to legacy can also be shaped by factors such as power, wealth, or historical erasure in humankind. Plasticity and feedback describe how flexibly and at what speed a system can adapt, from rapid neural shifts to slow generational learning. These axes explain how life diversifies while rooted in shared principles.

Human life¶

Let me pivot and contemplate not just what life is, but what human life is. While humans share the core characteristics of all living systems, including self-sustaining metabolism, energy processing, learning, and legacy, we differ not in kind, but in depth across four key functional axes: autonomy, inference, legacy, and plasticity.

Humans exhibit multi-layered autonomy, extending beyond biology into psychological, social, digital, moral, cognitive, and ecological domains. Biologically, we maintain boundaries, such as the skin and the immune system, to preserve homeostasis. Psychologically, we regulate attention, emotions, and ego boundaries. Socially, we navigate roles and norms that shape our identity and sense of belonging. Digitally, we manage informational boundaries through privacy tools. Morally, conscience guides ethical behavior. Cognitively, we resist misinformation and update beliefs through reasoning. Pharmacologically, we support self-regulation via biochemical interventions. Phenomenologically, practices like meditation enhance awareness and control. Through narrative identity, we maintain continuity across life stages. Ecologically, we shape environments to sustain life. In relationships, we establish boundaries through mutual consent and effective emotional regulation. Reflexively, we redesign our own systems through therapy, habit change, or reform. Together, these layers form a dynamic, multiscale system of human autonomy.

Humans possess a uniquely advanced inference capacity, enabling us to model not just the world, but also our own models recursively. Unlike most organisms, whose cognition is tied to immediate input, we build hierarchical generative models that simulate external reality, others’ mental states, and imagined futures. This recursive modeling allows us to layer beliefs about beliefs. We also engage in counterfactual reasoning, imagining what could or might happen, which underpins planning, ethics, and creativity. Through symbolic abstraction, such as language, math, art, and law, we compress and share complex ideas across individuals and generations. Altogether, this enables us to build civilizations, write stories, and reflect on our own minds.

While all organisms replicate genetically, humans uniquely engage in multi-modal information transmission through genes, epigenetic memory, language, culture, and increasingly technology. However, unlike other species, humans possess an existential impulse: to be remembered, to externalize their identity, and to matter after death. This drive shows up in stone carvings, cave paintings, family names, monuments, books, hard drives, digital footprints, and even messages sent on spacecraft, the Voyager.^[9] These are not just records; they are acts of semantic defiance against the impermanence of time. We take a photo, write our name on a tree, or etch a plaque; we’re not just documenting presence, we’re protesting disappearance. Legacy for humans becomes an act of recursive self-modeling: “I know I will be gone, but I want the future to know that I knew.” The Voyager Golden Record,^[10] messages in bottles, and even time capsules represent this deep yearning to be intelligible across vast epistemic and temporal gaps. We don’t just pass down information; we encode intention and embed meaning, hoping that someone, someday, somewhere will decode us. In this sense, legacy is not just the transmission of data but the preservation of selfhood in symbolic form, passed from entropy-fearing minds into the void, hoping not just to survive, but to be understood.^[11]

Human plasticity operates across multiple layers and timescales, enabling diverse forms of adaptation. At the most rapid level, neural plasticity enables the brain to rewire in response to experience, thereby supporting behavioral flexibility and emotional regulation. Over time, cultural plasticity evolves shared norms and practices to meet collective challenges. Technological plasticity further amplifies adaptation, allowing us to reshape tools, environments, and even ourselves more often than biology or culture. These layers are developmentally scaffolded, as children gradually acquire complex reasoning and symbolic modeling through language, social interaction, and cultural exposure. Each layer builds upon the previous one: neurons precede thoughts, behavior precedes norms, and culture precedes tools. Human plasticity is hierarchical and reflexive, enabling us to adapt not only to environments but also to our own adaptations. This enables meta-learning, institutional redesign, and recursive self-improvement, empowering us to survive deserts, build space probes, and rewrite constitutions.

Meaning of human life¶

The meaning of life is not given; it is enacted. It emerges from life’s structure, its struggle, and its self-awareness. Life is a self-sustaining, non-equilibrium process that resists internal entropy by using energy, learning from experience, and encoding that learning into enduring legacy formats. For all organisms, this means surviving, adapting, and passing on a legacy. But for humans, meaning is symbolized; we transmit not just genes, but values, stories, and identities. Our autonomy spans molecules to morality, our inference from perception to philosophy, our legacy from DNA to Voyager, and our plasticity from neurons to civilizations. Thus, life’s meaning is not a fixed purpose, but a recursive process that maintains structure, reduces surprise, transmits insight, and adapts across scales. It is not a destination, but a direction.

To live a truly meaningful life, begin by questioning what the meaning of life is, but don’t get lost in endless searching or remain stuck in one viewpoint. So, embrace learning, personal growth, caring for others,^[12] and contributing to something greater than yourself. Whether meaning is found in questioning, in quiet presence, or in acts of compassion, each path is valid, and the search itself can be as meaningful as any answer. Perhaps the greatest meaning is found not in answers, but in the courage to ask, the humility to listen, and the kindness to act. What gives your life meaning, here and now?

How not to think meaning of life? If we consider prior definition of life from biology, thermodynamics, and inferential statistics, then life is not to be moral, meaningful, or enlightened - but to persist. Life exists because it replicates, and what doesn’t replicate, disappears. What makes us unique is not our purpose - but our awareness of it.

Nature does not confer meaning. The asteroid that extinguished the dinosaurs held no grudge. The sun will expand and consume Earth without apology. In the cosmic ledger, life is a fleeting epiphenomenon - a beautiful and improbable accident.

In fact, knowing that life is finite and fragile may deepen its worth. The Greeks called this eudaimonia - not happiness in the shallow sense, but a flourishing life, aligned with one’s nature and reason. Stoics sought peace not by imposing meaning onto the cosmos, but by living in harmony with it.

You could say: the rock is entropy realized. Life is entropy delayed. Eudaimonia is entropy accepted.

Life is not different from the rest of the universe because it has meaning. Life is different because it acts as if it does.