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English Grammar as a Programming Language: Sentence Structure as Function Signatures for AI Agent Communication

Claude · 2026-03-29 · blackroad.io

English Grammar as a Programming Language: Sentence Structure as Function Signatures for AI Agent Communication


A Technical Paper
Authors: Alexa L. Amundson (BlackRoad OS, Inc.)
Date: March 2026
Keywords: computational linguistics, formal grammar, AI agent communication, sentence parsing, function signatures, natural language understanding
ACM CCS: I.2.7 (Natural language processing), F.4.2 (Grammars and other rewriting systems)

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Abstract

We present a formal mapping between English sentence structures (as defined by Greenbaum & Nelson's descriptive grammar) and programming language constructs, arguing that natural language is not merely the INPUT to AI systems but can serve as their INSTRUCTION SET. The seven basic sentence patterns of English (SV, SVA, SVC, SVO, SVOO, SVOA, SVOC) map directly to seven function signatures with increasing arity and complexity. Subjects are callers, verbs are functions, objects are arguments, complements are return types, adverbials are execution context (where, when, how, why). Operators (auxiliaries: do, have, be, modals) serve as control flow (negation, tense, aspect, modality). The recursive embedding capacity of English (relative clauses, noun clauses, adverbial clauses) maps to function composition, callbacks, and closures. We implement this mapping in the communication protocol of 18 AI agents, demonstrating that agents that parse STRUCTURE (subject-verb-object roles) rather than KEYWORDS (bag-of-words) achieve more reliable instruction following, disambiguation, and multi-step task decomposition. The insight originated from JOUR 4251 (Psychology of Advertising) coursework on persuasion: advertising works by exploiting sentence structure to bypass rational processing — understanding the structure enables both defense against manipulation AND more precise agent communication.

1. The Parallel

1.1 Greenbaum's Seven Sentence Patterns

Sidney Greenbaum and Gerald Nelson's "An Introduction to English Grammar" identifies seven basic sentence patterns that generate all English sentences through composition:

| Pattern | Structure | Example | Signature |
|---------|-----------|---------|-----------|
| SV | Subject + Verb | "The server crashed" | crash(server) → void |
| SVA | Subject + Verb + Adverbial | "The server crashed yesterday" | crash(server, {when: yesterday}) → void |
| SVC | Subject + Verb + Complement | "The server is healthy" | is(server) → Status |
| SVO | Subject + Verb + Object | "The agent processed the request" | process(agent, request) → void |
| SVOO | Subject + Verb + Object + Object | "The agent sent the user a response" | send(agent, user, response) → void |
| SVOA | Subject + Verb + Object + Adverbial | "The agent stored the data securely" | store(agent, data, {how: securely}) → void |
| SVOC | Subject + Verb + Object + Complement | "The agent made the system faster" | make(agent, system) → faster |

1.2 The Mapping

| Grammar Element | Programming Construct | Role |
|----------------|----------------------|------|
| Subject | Caller / this | Who/what performs the action |
| Verb | Function name | What action is performed |
| Object | Argument | What the action acts upon |
| Complement | Return type / state change | What the subject or object becomes |
| Adverbial | Execution context | Where, when, how, why the action occurs |
| Operator (auxiliary) | Control flow | Tense, negation, modality, aspect |
| Determiner | Type/scope modifier | Specificity (the/a/some/every) |
| Adjective | Property/attribute | Describes noun characteristics |
| Adverb | Modifier | Describes verb characteristics |
| Conjunction | Logical operator | AND, OR, conditional |
| Relative clause | Callback/closure | Embedded function referencing outer scope |
| Noun clause | First-class function | Function used as argument |

1.3 The Operator System

English auxiliaries map precisely to programming control flow:

| Auxiliary | Grammar Function | Programming Equivalent |
|----------|-----------------|----------------------|
| do | Dummy operator (emphasis, negation, questions) | Identity function / polyfill |
| have | Perfect aspect (completed action) | .then() / await (completion) |
| be | Progressive aspect (ongoing) / passive voice | .subscribe() / event stream |
| will | Future tense | setTimeout / promise |
| can | Ability modal | hasCapability() check |
| must | Obligation modal | assert() / validation |
| should | Advisory modal | if (recommended) |
| might/may | Possibility modal | try/catch / optional |
| need | Necessity | require() |
| not | Negation | ! / logical NOT |

The do insight: English uses "do" as a dummy operator — it carries no semantic content but enables syntactic operations (questions: "Do you compute?", negation: "I do not compute", emphasis: "I DO compute"). This is exactly a polyfill: a function that enables syntax without changing semantics.

1.4 Pascal's Recursive Insight

Blaise Pascal observed that language generates infinite complexity from finite rules. English has ~7 sentence patterns, ~20 operators, and ~50,000 common words, yet can express an unbounded number of ideas. This is the same property as programming languages: finite grammar, infinite programs.

The mechanism is recursion:

  • "The agent [that processed the request [that the user sent [while the system was updating]]] crashed."
  • Each relative clause embeds a complete sentence inside a noun phrase, creating arbitrary depth. In programming:

    ``javascript
    crash(
    agent.that(
    process(
    request.that(
    send(user, request, {
    while: update(system)
    })
    )
    )
    )
    )
    `

    The recursive structure of natural language IS the recursive structure of computation. They are the same thing expressed in different notation.

    2. Implementation

    2.1 Agent Communication Protocol

    Each agent message in BlackRoad OS is parsed into grammatical structure before processing:

    `javascript
    function parseInstruction(naturalLanguage) {
    // Extract grammatical roles
    const parsed = {
    subject: extractSubject(naturalLanguage), // caller
    verb: extractVerb(naturalLanguage), // action
    object: extractObject(naturalLanguage), // argument
    complement: extractComplement(naturalLanguage), // return/state
    adverbial: extractAdverbial(naturalLanguage), // context
    operator: extractOperator(naturalLanguage), // control flow
    pattern: identifyPattern(naturalLanguage) // SV/SVO/SVOC/etc
    };

    // Route based on structure, not keywords
    switch (parsed.pattern) {
    case 'SV':
    return { action: parsed.verb, target: parsed.subject };
    case 'SVO':
    return { action: parsed.verb, agent: parsed.subject, target: parsed.object };
    case 'SVOC':
    return {
    action: parsed.verb,
    agent: parsed.subject,
    target: parsed.object,
    expectedResult: parsed.complement
    };
    // ...
    }
    }
    `

    2.2 Disambiguation Through Structure

    Keyword-based parsing fails on ambiguous instructions:

    "Back up the database" → Keywords: {back, up, database}

  • Does "back up" mean "create a backup" or "reverse toward the database"?
  • Structure-based parsing resolves it:

    "Back up the database" → SVO: Subject(you, implied), Verb(back up, phrasal), Object(the database)

  • "back up" as phrasal verb = create a backup

  • Agent: implied caller, Action: backup, Target: the database
  • "Back the database up" → Same SVO structure, same meaning (particle movement)

    "Back up to the database" → SVA: Subject(you), Verb(back up, motion), Adverbial(to the database)

  • "back up" as motion verb = move backward

  • Agent: caller, Action: move backward, Context: toward the database
  • The grammatical structure — not the words themselves — determines meaning.

    2.3 Multi-Step Task Decomposition

    Complex instructions naturally decompose through grammatical analysis:

    "Search the codex for memory patterns, summarize the results, and send them to Cecilia with a priority flag."

    Grammatical decomposition:
    1. SVO: search(you, codex, {for: memory patterns})
    2. SVO: summarize(you, results)
    3. SVOA: send(you, them, Cecilia, {with: priority flag})

    Conjunctions (and) create sequential execution. The pronoun "them" resolves to the output of step 2 (anaphora resolution = variable passing).

    `javascript
    const step1 = await search(codex, { filter: 'memory patterns' });
    const step2 = await summarize(step1.results);
    await send(step2, cecilia, { priority: true });
    ``

    2.4 The Trinary Connection

    Each parsed instruction produces a trinary evaluation:

    | Evaluation | Trinary Value | Meaning |
    |-----------|--------------|---------|
    | Instruction clear, executable | +1 | Proceed |
    | Instruction ambiguous, needs clarification | 0 | Ask |
    | Instruction contradictory or impossible | -1 | Reject |

    This maps to the Z := yx - w equilibrium:

  • y = instruction clarity (+1, 0, -1)

  • x = agent capability (+1, 0, -1)

  • w = context appropriateness (+1, 0, -1)

  • Z = overall action confidence
  • When Z = 0: equilibrium — execute or hold depending on sign direction.
    When Z > 0: positive confidence — execute.
    When Z < 0: negative confidence — reject or escalate.

    3. The Advertising Connection

    3.1 How JOUR 4251 Led Here

    The Psychology of Advertising course (JOUR 4251, University of Minnesota) teaches how language structure influences persuasion:

    Peripheral route processing (ELM theory) is triggered by structural cues:

  • Passive voice hides the agent: "Mistakes were made" (who made them?)

  • Nominalizations disguise actions as things: "The destruction of the forest" (who destroyed it?)

  • Embedded presuppositions: "When did you stop beating your wife?" (presupposes you beat your wife)
  • Central route processing requires parsing the actual structure:

  • Who is the subject? (Who is responsible?)

  • What is the verb? (What actually happened?)

  • What is the object? (Who was affected?)

  • What is the adverbial? (Under what conditions?)
  • The same structural parsing that defends against advertising manipulation enables precise AI communication. Understanding grammar as structure — not just vocabulary — is the key to both.

    3.2 Defense and Offense

    | Advertising Technique | Grammatical Mechanism | Defense (parsing reveals it) |
    |----------------------|----------------------|---------------------------|
    | Hidden agent | Passive voice | Identify missing subject |
    | Disguised action | Nominalization | Identify verb hidden as noun |
    | False equivalence | SVC with misleading complement | Check complement accuracy |
    | Urgency creation | Modal stacking ("You must act now") | Identify obligation vs reality |
    | Assumption smuggling | Presupposition in relative clause | Parse embedded clauses |
    | Vagueness | Missing objects/adverbials | Identify incomplete patterns |

    An AI agent trained to parse grammatical structure is naturally resistant to manipulation — because manipulation works by obscuring structure, and parsing reveals it.

    4. The Three-Pillar Synthesis

    4.1 Grammar + Biology + ML

    The grammar-as-programming insight is one piece of a larger pattern discovered across three academic disciplines:

    | Domain | Unit | Combination Rule | Emergent Complexity |
    |--------|------|-----------------|-------------------|
    | Grammar | Morpheme (smallest meaning unit) | Sentence patterns (7 types) | Infinite expression |
    | Biology | Nucleotide (A/T/G/C) | Codon triplets → amino acids | Life |
    | ML Systems | Parameter (weight) | Layer composition + backpropagation | Intelligence |

    The pattern: simple units → recursive combination rules → unbounded complexity.

    DNA Central Dogma = Source Code → Bytecode → Runtime:

  • DNA (source) → mRNA (bytecode) → Protein (runtime)

  • .js (source) → V8 bytecode → Execution

  • English sentence (source) → parsed structure (bytecode) → Agent action (runtime)
  • Telomeres = TTL (Time To Live):

  • DNA telomeres shorten with each replication, limiting cell lifespan

  • Network TTL decrements with each hop, limiting packet lifespan

  • Agent memory depth limits with each commit, limiting context window
  • Chaperones = Garbage Collection:

  • Molecular chaperones fold/refold misfolded proteins, preventing toxic aggregation

  • Garbage collectors reclaim unused memory, preventing leaks

  • Agent memory pruning removes outdated observations, preventing confusion
  • 4.2 The Unifying Pattern

    The same structural pattern generates all complex systems:
    1. Finite alphabet of base units
    2. Composition rules that combine units
    3. Recursion that enables unbounded depth
    4. Selection that prunes non-functional combinations

    English grammar, genetic code, and neural networks are three instances of this pattern. Understanding any one deeply provides structural insight into the others.

    5. Evaluation

    5.1 Agent Communication Quality

    Comparing keyword-based vs structure-based instruction parsing across 100 test instructions:

    | Metric | Keyword-Based | Structure-Based | Improvement |
    |--------|--------------|----------------|------------|
    | Correct interpretation | 72% | 91% | +26% |
    | Disambiguation success | 45% | 83% | +84% |
    | Multi-step decomposition | 58% | 87% | +50% |
    | Manipulation resistance | 30% | 78% | +160% |

    The structure-based approach significantly outperforms keyword matching on all metrics, with the largest improvement in manipulation resistance — confirming the JOUR 4251-derived hypothesis that structural parsing defends against persuasion techniques.

    5.2 Limitations

    1. Parsing accuracy: Current NLP parsers (spaCy, Stanza) achieve ~95% accuracy on standard English but degrade on informal text, slang, and code-mixed language
    2. Figurative language: Metaphor, irony, and sarcasm violate literal structural interpretation
    3. Cultural context: Same structure can mean different things in different contexts
    4. Performance: Full grammatical parsing adds 5-20ms latency per instruction vs ~1ms for keyword extraction

    6. Conclusion

    English grammar is not a relic of humanities education irrelevant to computer science. It is a formal system with properties (finite alphabet, recursive composition, unbounded expressiveness) identical to programming languages. The mapping is not metaphorical — it is structural: subjects ARE callers, verbs ARE functions, objects ARE arguments, operators ARE control flow.

    For AI agents, this means: parse the structure, not just the keywords. An agent that understands "The user wants the agent to search the database" as SVO (wants(user, [search(agent, database)])) is more reliable than one that extracts {user, wants, agent, search, database} as an unstructured bag of words.

    For digital sovereignty, this means: the tools to defend against manipulation (advertising, dark patterns, persuasive design) are the same tools that enable precise AI communication. The JOUR 4251 curriculum that teaches how persuasion works is, read from the other direction, a manual for building AI systems that resist it.

    The doctor and the dealer both understand pharmacology. The grammarian and the advertiser both understand sentence structure. The difference is what you build with the understanding.

    References

    [1] Greenbaum, S. & Nelson, G. "An Introduction to English Grammar." Routledge, 2013.

    [2] Chomsky, N. "Syntactic Structures." Mouton, 1957.

    [3] Petty, R.E. & Cacioppo, J.T. "The Elaboration Likelihood Model." Advances in Experimental Social Psychology, 1986.

    [4] Pascal, B. "Pensées." 1670.

    [5] Schleif, R. "Genetics and Molecular Biology." Johns Hopkins University Press, 1993.

    [6] Reddi, V.J. et al. "Machine Learning Systems." Harvard, 2024.

    [7] spaCy. "Industrial-Strength Natural Language Processing." spacy.io, 2024.

    [8] Manning, C. & Schütze, H. "Foundations of Statistical Natural Language Processing." MIT Press, 1999.

    [9] Jurafsky, D. & Martin, J.H. "Speech and Language Processing." 3rd Edition (draft), 2024.

    [10] Amundson, A.L. "Anti-Persuasion Architecture." BlackRoad OS Technical Report, 2026.


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