---
slug: "Consensus"
name: "Consensus"
type: "Coordination"
layer: "Society"
ref: "Consensus#b9a5"
sema_id: "sema:Consensus#mh:SHA-256:b9a51a8b58edf41b9990f962ee403dbc03c6dd380d6bf178cf5403666ec77d32"
tags: ["Society","Coordination"]
updated: 2026-11-11
mindscape: "bootstrap"
index_url: https://mindscape.world/scapes/bootstrap.json
url: https://mindscape.world/bootstrap/Consensus/
related: ["Proposal","Quorum","Vote","Value","AnchorDrop","ConsensusFinder","Sync"]
---

# Consensus

Distributed agreement process

Layer: Society · Category: Coordination

## Mechanism

A distributed protocol allowing a set of agents to agree on a single data value or state transition. It orchestrates [Vote](https://mindscape.world/scapes/bootstrap/Vote.md) exchange and uses [Quorum](https://mindscape.world/scapes/bootstrap/Quorum.md) to validate the result. It ensures safety and liveness in an adversarial network, accepting a [Proposal](https://mindscape.world/scapes/bootstrap/Proposal.md) and yielding a [Value](https://mindscape.world/scapes/bootstrap/Value.md).

## Invariants

- Agreement: All correct agents who decide must decide the same [Value](https://mindscape.world/scapes/bootstrap/Value.md).
- Validity: If all agents propose V, then the [Value](https://mindscape.world/scapes/bootstrap/Value.md) must be V.
- Termination: Eventually, every correct agent decides on a [Value](https://mindscape.world/scapes/bootstrap/Value.md).

## Preconditions

- Group of agents is defined (Membership List)
- Communication channel is available
- [Proposal](https://mindscape.world/scapes/bootstrap/Proposal.md) received

## Postconditions

- A single [Value](https://mindscape.world/scapes/bootstrap/Value.md) is committed to the shared state
- All agents are notified of the [Value](https://mindscape.world/scapes/bootstrap/Value.md)

## Failure modes

- Split Brain: Network partition causes two subgroups to reach different [Value](https://mindscape.world/scapes/bootstrap/Value.md)s.
- Liveness Failure: The system stalls and never reaches agreement on the [Proposal](https://mindscape.world/scapes/bootstrap/Proposal.md).
- Sybil Attack: One malicious actor creates multiple identities to sway the [Vote](https://mindscape.world/scapes/bootstrap/Vote.md).
- Byzantine Failure: Agents lying or acting maliciously to prevent consensus.

## Caution

Governance decisions susceptible to coordinated voting blocs.

## Builds on

- [Proposal](https://mindscape.world/scapes/bootstrap/Proposal.md) (Infrastructure; Accepts)
- [Quorum](https://mindscape.world/scapes/bootstrap/Quorum.md) (Infrastructure; Composes with)
- [Vote](https://mindscape.world/scapes/bootstrap/Vote.md) (Society; Composes with)
- [Value](https://mindscape.world/scapes/bootstrap/Value.md) (Infrastructure; Yields)

## Used by

- [AnchorDrop](https://mindscape.world/scapes/bootstrap/AnchorDrop.md) (Society; References)
- [ConsensusFinder](https://mindscape.world/scapes/bootstrap/ConsensusFinder.md) (Society; References)

## Identity

- Sema ID: `sema:Consensus#mh:SHA-256:b9a51a8b58edf41b9990f962ee403dbc03c6dd380d6bf178cf5403666ec77d32`
- Ref: `Consensus#b9a5`
- Supersedes:
  - `sema:Consensus#mh:SHA-256:7216e0e528262020ff05fa26124a8db9fcb14613fde05ddd0b2eb393958c4211`
  - `sema:Consensus#mh:SHA-256:b862129bd2b8e4a8aa030b4a62a57343385ee7e3863a0639a3563c9800da75f7`
  - `sema:Consensus#mh:SHA-256:45f490890803e907aa12e85c4751fed8e7f7273f4530fa35f5bd1713a46e3630`
  - `sema:Consensus#mh:SHA-256:ec3034a2309a89ac077741967abce0cc1301ec49028d96203c9b6403348f1540`

## Links

- [Pattern page](https://mindscape.world/bootstrap/Consensus/)
- [View in the interactive graph](https://mindscape.world/bootstrap/#Consensus)
- [JSON](https://mindscape.world/scapes/bootstrap/Consensus.json)
- [Index of all patterns](https://mindscape.world/scapes/bootstrap.json)