12 January 2026

Reconciling Ontologies and Taxonomies

In the modern knowledge economy, the proliferation of specialized vocabularies—ranging from deeptech semiconductor taxonomies to urban air mobility ontologies—has created a semantic silos problem. To enable interoperability, organizations must reconcile these disparate models. While the Simple Knowledge Organization System (SKOS) provides a flexible framework for representing taxonomies and thesauri, integrating it with more rigorous OWL (Web Ontology Language) derivatives requires a sophisticated ecosystem of open-source tools. Moreover, reconcilation requires a hybrid approach between the symbolic logic (exact, rule-based) with probabilistic machine learning (contextual, flexible).

Modern reconciliation begins with probabilistic methods to bridge the semantic gap. Large Language Models (LLMs) serve as powerful semantic matchers, using zero-shot reasoning to identify that a "Power MOSFET" in a semiconductor taxonomy is functionally equivalent to an "Electronic Switch" in a drone's propulsion ontology. However, LLMs lack structural awareness.

To resolve this, Graph Neural Networks (GNNs) are employed to capture the topology of the knowledge graph. By using message-passing architectures, GNNs generate node embeddings that reflect not just the name of a concept, but its position within the hierarchy. This allows for Link Prediction and Entity Resolution based on structural similarity—if two concepts share similar neighborhoods in their respective graphs, they are likely candidates for reconciliation.

Once probabilistic candidates are identified, symbolic methods provide the necessary sanity check. The first step in reconciliation is identifying correspondences between entities. AgreementMakerLight (AML) and LogMap are the primary open-source engines for this task. AML excels at large-scale lexical matching, using advanced string-similarity algorithms and background knowledge to find equivalent terms. LogMap, developed at the University of Oxford, adds a layer of built-in reasoning. Unlike simple matchers, LogMap detects and repairs logical inconsistencies on the fly, ensuring that the resulting mapping does not lead to unsatisfiable classes when the systems are integrated.

For those requiring deeper semantic linking, Silk (the Link Discovery Framework) is an essential tool. Silk allows developers to specify complex rules for discovering links between data items in different repositories, making it ideal for connecting a specific semiconductor part in one database to its application in a drone system in another.

Reconciliation often requires moving data between different formats. LinkML (Linked Data Modeling Language) has emerged as a powerful, tool-agnostic modeling framework. It allows users to define their schema in YAML and automatically generate SKOS, OWL, or even JSON-Schema, providing a single source of truth for diverse representations.

To physically transform non-RDF data into a reconciled knowledge graph, the RML (RDF Mapping Language) framework is the open-source standard. RML allows for the definition of mapping rules that can ingest CSVs, JSON, or SQL databases and output standardized SKOS concepts, ensuring that legacy taxonomies can participate in the semantic web.

A reconciled ontology is only useful if it is accurate and logically sound. SHACL (Shapes Constraint Language) provides the contract for the data. By defining SHACL shapes, developers can validate that the reconciled graph adheres to specific structural requirements (e.g., "every Drone must have exactly one FlightController chip").

For developers building custom reconciliation pipelines, rdflib is the foundational Python library. It provides the programmatic tools to parse, query (via SPARQL), and manipulate RDF and SKOS data. By combining rdflib for manipulation and a SHACL validator for integrity, engineers can automate the merging of taxonomies with high precision.

The reconciliation of knowledge representations is no longer a manual task of matching words. By leveraging the speed of AML, the logical rigor of LogMap, the structural flexibility of LinkML, and the validation power of SHACL, organizations can build a unified Semantic Bridge. This open-source stack ensures that even the most complex deeptech domains can speak a common language, turning isolated data points into a cohesive, actionable knowledge graph. The reconciliation of ontologies is no longer a choice between human-curated logic and AI-driven guesses. By using LLMs and GNNs to discover potential bridges and SHACL and LogMap to verify them, organizations can build knowledge graphs that are both contextually rich and logically sound. This neural-symbolic synergy is the only way to scale the nervous systems of complex industries like deeptech and autonomous mobility.