Why Definitions Matter
Most AI projects fail not because the technology does not work, but because no one agreed on what the system was supposed to mean. Teams build pipelines, train models, and deploy agents while quietly disagreeing about what a "customer" is, what "current" means, or whether a transaction that was reversed still counts. The system runs. The results are wrong. And no one can explain why, because the meaning was never made explicit.
This article offers working definitions of three terms that get conflated constantly in enterprise AI: data, information, and knowledge. More importantly, it explains what I mean by semantics, because that word in particular has been stretched to cover so many things that it has stopped being useful.
These definitions draw on three sources: Charles Sanders Peirce's semiotics, Ludwig Wittgenstein's philosophy of language, and Ronald Stamper's semiotic ladder as adapted by Jan Dietz in his work on Enterprise Ontology. The goal is not to settle philosophical debates. The goal is to give architects, AI designers, and product teams a vocabulary precise enough to build on.
These are working definitions. I find them useful for thinking clearly about information and knowledge-based systems.
The Semiotic Ladder: How Meaning Emerges in Layers
Ronald Stamper developed the semiotic ladder as part of his work on Organizational Semiotics, extending the classical syntax/semantics/pragmatics division from Charles Morris. Jan Dietz further adapted this ladder for Enterprise Ontology and DEMO, adding the physical and social layers. It offers a useful way to understand how meaning builds up in layers. Each level depends on the one below it. If you try to skip levels, you end up assuming things that were never actually provided. Each level contributes something the lower levels simply do not have.
Dietz groups these levels into three categories. The lower levels (empirics and syntax) concern form: how signs are encoded and structured. The middle levels (semantics and pragmatics) concern content: what signs mean and why they are used. The top level (social) concerns commitment: the shared agreements that make communication binding. Dietz calls these forma, informa, and performa.
This ladder makes something clear: you cannot reach knowledge by operating only at the semantic level. Semantics gives you meaning, but meaning without intent and social context is inert. It does not act. It does not commit. It does not know.
This is why simplistic equations like "knowledge = data + semantics" fail. They skip levels. I will propose an alternative formulation after explaining what I mean by semantics.
Data: Signals Before Interpretation
Data sits at the bottom of our ladder. It is raw symbols without structured meaning: the bytes, the signals, the uninterpreted marks.
Data is necessary but not interesting on its own. It becomes something more only when we impose structure (moving to syntax) and interpretation (moving to semantics). The mistake many systems make is treating data as if it were already meaningful, as if collecting and storing something automatically makes it significant.
Data is what you have before you have made any conceptual commitments. It is the material from which meaning will be constructed, not meaning itself.
Semantics: Conceptual Distinctions, Not Closed Truth
Here is where clarity matters most.
Semantics is the disciplined articulation of conceptual distinctions, expressed in a conceptual schema, that supports shared reference, reasoning, and the possibility of coordinated action. Its validity emerges through use, correction, and contextual interpretation, not through prior closure.
Two philosophical perspectives inform this definition.
Peirce: Meaning Is Triadic
Charles Sanders Peirce argued that meaning is not a simple two-way relationship between a word and a thing. It is triadic:
- Sign: the form the sign takes (a word, an image, a symbol)
- Object: what the sign refers to (which may be real or modeled)
- Interpretant: the understanding or effect the sign produces in an interpreter
The interpretant is the key element. Meaning does not exist in the sign alone, nor in the object alone. Meaning exists in the relationship between sign, object, and interpretation. Without an interpreter, human or otherwise, there is no meaning.
This has direct consequences for so-called "semantic systems." An OWL ontology or RDF graph contains signs and structural relationships. But the interpretant, the meaning, arises only when something interprets those signs in a context of use. The system itself does not "understand" its contents any more than a dictionary understands the words it contains.
Peirce also insisted that referents can be "real or modeled." Not everything a sign refers to must exist in the physical world. Some referents exist because we model them: legal entities, social roles, abstract categories. Their meaning stabilizes through use, not through correspondence to physical objects.
This is why I prefer the term conceptual schema over ontology. Ontology, in its philosophical sense, asks "what exists?" and tends toward fixed, truth-asserting commitments. A conceptual schema asks "what distinctions matter for our purposes?" and allows for provisional, revisable, purpose-relative modeling.
Wittgenstein: Meaning Is Use
Ludwig Wittgenstein argued that, for most cases, the meaning of a word is best understood as its use in the language. Words do not carry meaning like containers. They acquire meaning through participation in structured activities, what he called "language games."
This has practical implications. Meaning is not fixed at design time. A conceptual schema is not validated when you draw it or formalize it. It is validated when:
- It supports queries that answer real questions
- It enables decisions that work in practice
- It survives domain change without breaking
- It fails usefully and gets corrected
Semantics is therefore intended at modeling time, where we aim for certain meanings, but tested at runtime, where we discover whether those meanings actually hold up in practice. This directly contradicts any demand for "deterministic semantic termination," the idea that meaning should be closed, complete, and self-executing.
This does not deny the value of formal semantics. It situates formal semantics within practice rather than above it.
What Semantics Is Not
Given this understanding, we can state precisely what semantics is not:
- Semantics is not closed. There is no final, complete specification of meaning that eliminates interpretation. Meaning evolves. Language drifts. Contexts change.
- Semantics is not absolute. Meaning is always relative to a purpose, a community, a situation. The same term can mean different things in different contexts, and this is not a failure but a feature of how language works.
- Semantics is not self-executing. Semantics supports the potential for action, but knowing what something means does not automatically tell you what to do about it. Meaning must be connected to intent before it determines action.
- Semantics is not truth. A conceptual schema can be internally consistent and factually wrong. Logical consistency is not the same as correspondence to reality. Models represent distinctions we have chosen to make, not reality as it necessarily is.
Information: Semantics Without Intent
If semantics is meaning, then information is structured meaning that can be communicated, stored, and reasoned over, but that lacks the pragmatic dimension of purpose.
Information tells you what. It does not tell you why or what to do.
Consider the statement: "Person X has birth date January 15, 1990." This is information. It has semantic content. We know what "Person," "birth date," and "January 15, 1990" refer to. But the information alone does not tell us why we are tracking this, what we should do with it, or what commitments follow from it.
The same information might serve multiple purposes:
- Verifying eligibility for a service (intent: access control)
- Calculating benefits (intent: financial determination)
- Detecting fraud (intent: risk mitigation)
The semantics remain the same. The intent changes.
The same is true of axioms, constraints, and business rules. They add structure and discipline to meaning, and they can be evaluated or enforced, but they still do not supply purpose. A rule can be correct and executable and still not be knowledge.
Information is semantics without commitment or intent. Execution does not change that.
Knowledge: Semantics + Intent + Social Context
Knowledge adds what information lacks: purpose, commitment, and grounding in practice.
Knowledge is not merely structured meaning. It is meaning that has been:
- Connected to intent. Knowledge serves goals. It exists within a context of action and decision.
- Validated through use. Knowledge is tested after the fact. Did it work? Did it enable good decisions? Did it survive challenge?
- Embedded in social practice. Knowledge is shared, maintained, and evolved by communities. It carries weight about what matters, not just what is true.
This is why knowledge requires the full semiotic ladder. You cannot have knowledge operating only at the semantic level. You must also engage the pragmatic level (intent, goals, purpose) and the social level (norms, roles, shared commitments).
Knowledge is what happens when semantics becomes actionable within a community of practice.
Now we can state the formula properly:
Knowledge = (Symbols + Structure + Shared Meaning) × Intention
The multiplication sign matters. Without intention, the other components remain latent, present but not activated into something we would recognize as knowledge. That is also the bridge to the governance question taken up in Intent-Driven AI Delegates, where intention is treated not as a slogan but as an explicit architectural constraint.
Peirce and Wittgenstein converge here. For Peirce, the interpretant of a knowledge system is operational: knowledge systems are validated by what they enable, by decisions, actions, and coordinations. For Wittgenstein, understanding is not a mental state prior to action but something that shows up in action. To know is to be able to go on, to use the knowledge appropriately in new situations.
Why This Matters for AI
These distinctions have direct consequences for how we design AI systems, and specifically for where we put LLMs in the architecture.
Most systems marketed as "semantic AI" are operating at the structural or logical level. They provide formal syntax, consistency checking, and inference over asserted propositions. Those are valuable capabilities. But they are not semantics in the sense described here. They lack the interpretant. They lack validation through use. They lack the connection to intent. Calling them semantic creates false expectations about what they can guarantee and who is responsible when they get it wrong.
LLMs fit into a well-grounded AI architecture as interpreters, not authorities. They are good at mapping ambiguous natural language to known conceptual elements, surfacing candidate meanings, and flagging missing context. That is genuinely useful. But an LLM does not define what terms mean in your domain. It does not enforce constraints. It does not decide who has authority to act. And it cannot be held accountable for outcomes.
The missing layers in most AI system designs are not technical. They are: intent, which defines what purpose the AI is actually serving; accountability, which defines who is responsible when the AI acts; and human judgment, which defines what cannot be delegated at all. A conceptual schema, no matter how rigorous, cannot answer those questions. Neither can an LLM. They require explicit modeling of intent, delegation, and governance, which is the subject of the companion article on Intent-Driven AI Delegates.
Conclusion: Semantic Honesty as Practice
Semantics is not a property you achieve once at design time. It is a practice you maintain as the system runs, as the domain changes, and as use reveals gaps that modeling could not anticipate.
The semiotic ladder makes the stakes clear. Data becomes information when it is structured. Information becomes actionable when it is connected to intent. Action becomes responsible when it is embedded in a social context with clear lines of accountability. Skip any of those steps and you have a system that runs but does not know what it is doing or why.
For AI systems specifically, this means three things. First, stop calling systems semantic when they are really syntactic. The label raises expectations the system cannot meet. Second, make intent explicit. It does not emerge from data on its own, and burying it in code makes it invisible to governance and audit. Third, keep human accountability in place, not because AI is untrustworthy, but because accountability is a social act that only persons can perform.
These are not abstract principles. They are design constraints. Applied consistently, they produce AI systems that are auditable, governable, and resilient to the domain change that every enterprise eventually faces. The companion article on Intent-Driven AI Delegates shows what that looks like in practice, and the prototype work at knowledge-foundation.ai shows what it looks like running.