Definition
Social capital is the value embedded in social networks and relationships — the trust, norms of reciprocity, mutual support, and sense of connection that being part of a community makes available as a usable resource. It can be held by individuals, in the form of their personal ties, and by communities, in the form of their collective cohesion.
Sapolsky draws on social capital to explain why social connection matters for health and behavior, and why the texture of a community — not just the wealth of its members — shapes outcomes.
Why it matters
How it works
Social capital accumulates through repeated, trustworthy interaction. When people in a community help one another, keep promises, and expect reciprocity, they build a shared stock of trust that lowers the cost of cooperation and provides support in hard times.
Sapolsky highlights that this stock has measurable consequences. Communities rich in social capital tend to be healthier and less violent, and individuals with strong supportive ties show better-regulated stress physiology. The same connective tissue, though, can harden a boundary — bonding capital that unites an in-group can also wall off everyone outside it.