Sets are first-class
Set-builder notation, comprehensions, and the full algebra of sets — straight from the page into the runtime.
nums: [1, 2, 3, 4, 5, 6] { n | n <- nums, n mod 2 == 0 } ⇒ {2, 4, 6}
State what is true. Let the language reason.
A cognitive programming language for knowledge representation and reasoning — sets, logic, and many-valued truth, with a natural-language syntax that runs entirely in your browser.
Most languages compute with numbers. Axioma computes with truth.
Axioma reads like mathematics and runs like a program. Each construct below is real, executable syntax — try any of it in the playground.
Set-builder notation, comprehensions, and the full algebra of sets — straight from the page into the runtime.
nums: [1, 2, 3, 4, 5, 6] { n | n <- nums, n mod 2 == 0 } ⇒ {2, 4, 6}
Universal and existential quantifiers range over sets and evaluate to a truth value — ∀ and ∃, as code.
forall x in {2, 4, 6} | x mod 2 == 0 ⇒ true exists x in {1, 2, 3} | x > 2 ⇒ true
Declare facts and Horn-clause rules; recursion computes the full transitive closure, Datalog-style.
ancestor(X, Z) :- parent(X, Z) ancestor(X, Z) :- parent(X, Y) and ancestor(Y, Z)
Boolean, Kleene K3, Łukasiewicz L3, Belnap B4, and Gödel G3 — first-class logics for the unknown and the contradictory.
belnap("both") ⇒ ⊤⊥ om or true ⇒ true # unknown ∨ true
Russell's copula, made precise: identity, predication, and existence — with concepts, instances, and classification.
concept Stock { price: 0 } aapl: a Stock { price: 150 } aapl is Stock ⇒ true
The whole interpreter compiles to WebAssembly — no install, no server. It also speaks Forth-style stacks and prose-like definitions.
# a function, REBOL-style binding sq: func(n) [n * n] map(sq, [1, 2, 3]) ⇒ [1, 4, 9]
Real knowledge is incomplete and sometimes contradictory. Axioma builds that in: Belnap's four-valued bilattice treats missing and conflicting information as first-class truth values.
Contradiction propagates through rules instead of crashing — and every derived fact carries its epistemic grounding, from axiom down to hypothesis.
Axioma is a cognitive programming language — built for knowledge representation, symbolic reasoning, and explainable AI. After procedural, object-oriented, functional, and logic programming comes a fifth paradigm, whose defining act is to understand: to model a thing into a model of everything. Seventeen logics and eight knowledge-representation systems, unified under a single old dream.
“Calculemus. Let us calculate.”— G. W. Leibniz, on settling every dispute by computation
characteristica universalis + calculus ratiocinator — a universal language of thought, and a calculus to reason in it.
The Laws of Thought — the algebra of logic.
Begriffsschrift — the first formal logic; quantifiers, sense & reference.
Types, definite descriptions, and the three meanings of “is.”
Incompleteness — and numbering a formal system within itself.
Programs with common sense.
The cognitive language — 17 logics and 8 knowledge-representation systems, executable in your browser.
The interpreter runs in your browser — write a comprehension, prove a theorem, watch a rule reach its fixpoint.
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