# Substitutability

> Validate that every implementation of an abstraction preserves the abstraction’s behavior, accepts valid parent inputs, returns valid parent outputs, and does not strengthen forbidden constraints.

Record: `algorithms:substitutability`
Kind: algorithm
Canonical: https://banes-lab.com/ontology/algorithms#algorithms-substitutability
Closure: https://banes-lab.com/json/records/algorithms/substitutability/closure

Listed in [Algorithm contracts](https://banes-lab.com/api/records/algorithms.md), after [Interface Contract](https://banes-lab.com/records/algorithms/interface-contract.md) and before [Canonical Data](https://banes-lab.com/records/algorithms/canonical-data.md).

## Domain

- [Architecture](https://banes-lab.com/records/algorithms-domain/architecture.md)

## Tier

- [leaf](https://banes-lab.com/records/vocabulary/domain-tier-leaf.md)

## Math type

- [Logic](https://banes-lab.com/records/reasoning/math-type-logic.md)

## Force

- [Contract compatibility](https://banes-lab.com/records/force/contract-compatibility.md)
- [Correctness verification](https://banes-lab.com/records/force/correctness-verification.md)

## Contract of

- [Substitutability](https://banes-lab.com/records/lexicon/substitutability.md)

## Linked from

- [Quality Attributes](https://banes-lab.com/ontology/lexicon/lexicon-category-quality-attributes.md)
- [The mathematics](https://banes-lab.com/ontology/reasoning/the-mathematics.md)
- [Domain tiers](https://banes-lab.com/ontology/schema/the-vocabulary-domain-tier.md)
- [The forces](https://banes-lab.com/ontology/schema/the-forces.md)