Reasoning & Inference

This example demonstrates Fluree's reasoning capabilities using a biological taxonomy. You'll learn how to define rules that automatically infer new facts from your data—a powerful feature for knowledge graphs and ontology-driven applications.

The Scenario

A wildlife research database needs to:

• Classify organisms using a taxonomic hierarchy (Kingdom → Class → Order → Family)
• Infer that a Tiger is a Mammal (even if only typed as Feline)
• Define symmetric relationships (if A is related to B, then B is related to A)
• Define inverse relationships (if A eats B, then B is eaten by A)
• Query inferred facts alongside asserted facts

Schema Overview

graph TB Animal --> Mammal Animal --> Bird Animal --> Reptile Mammal --> Carnivore Mammal --> Herbivore Mammal --> Primate Mammal --> Rodent Carnivore --> Feline Carnivore --> Canine Bird --> Raptor

Taxonomic Hierarchy

Each class in the hierarchy is defined using rdfs:subClassOf:

{

"id": "bio:classes/Feline",

"type": ["rdfs:Class", "bio:TaxonomicClass"],

"rdfs:label": "Feline",

"rdfs:subClassOf": { "id": "bio:classes/Carnivore" }

}

When reasoning is enabled, a Tiger (typed as Feline) is automatically inferred to be:

• A Carnivore
• A Mammal
• An Animal

OWL Property Types

Fluree supports several OWL property types for automatic inference:

Property Type	Behavior
owl:TransitiveProperty	If A→B and B→C, then A→C
owl:SymmetricProperty	If A→B, then B→A
owl:InverseProperty	If A→B via prop1, then B→A via prop2

Example: Inverse Properties

{

"id": "bio:properties/eats",

"type": ["rdf:Property", "owl:ObjectProperty"],

"rdfs:label": "eats"

},

{

"id": "bio:properties/eatenBy",

"type": ["rdf:Property", "owl:ObjectProperty"],

"owl:inverseOf": { "id": "bio:properties/eats" }

}

When you assert "Lion eats Deer", the system automatically infers "Deer eatenBy Lion".

Example: Symmetric Properties

{

"id": "bio:properties/relatedTo",

"type": ["rdf:Property", "owl:ObjectProperty", "owl:SymmetricProperty"]

}

If you assert "Lion relatedTo Tiger", the inverse "Tiger relatedTo Lion" is automatically inferred.

Organisms in the Dataset

Organism	Class	Habitat	Conservation
Lion	Feline	Grassland	Vulnerable
Tiger	Feline	Forest	Endangered
Wolf	Canine	Forest	Least Concern
Arctic Fox	Canine	Arctic	Least Concern
Elephant	Herbivore	Grassland	Vulnerable
Chimpanzee	Primate	Forest	Endangered
Bald Eagle	Raptor	Forest	Least Concern
King Cobra	Reptile	Forest	Vulnerable

What You'll Learn

In the following pages, you'll explore:

1. Defining Rules - Create OWL properties and class hierarchies
2. Querying Inferred Data - Query both asserted and inferred facts

info

Reasoning enables you to store minimal facts and let the system derive additional knowledge, reducing data duplication and ensuring consistency.