# Apriori

> *"We cannot cognize things as they are in themselves, but only as they appear to us —*
> *through the a priori forms of intuition and understanding."*
> - Immanuel Kant, *Critique of Pure Reason*

**Apriori** is the transcendental optics of systematic cognition — the definition
of forms and modes through which a system can order and comprehend phenomena.

## De Aprioritate (On A Priori Nature)

According to Kant, we do not perceive the world immediately, but always through
*a priori forms* of our intuition and understanding. Space and time are forms of
sensibility; categories (unity, plurality, causality) are forms of understanding.
Without these forms, cognition is impossible.

**Apriori** applies this philosophy to systematic cognition: it defines
**transcendental categories** without which a system cannot cognize phenomena.

## Tres Elementa (Three Elements)

- **`Apriori.Phaenomenon`** — *quod apparet* (what appears)  
  The event before interpretation. Analog of sensation: pure datum, not yet formed.

- **`Apriori.Forma`** — *in qua forma significatio tenetur* (in what form meaning is held)  
  Analog of forms of intuition: `Essentia` (unity), `Collectio` (plurality),
  `Absentia` (negation), `Sententia` (judgment).

- **`Apriori.Modus`** — *genus actus cognitionis* (kind of cognitive act)  
  Analog of functions of judgment: `Quaestio` (theory), `Intentio` (praxis),
  `Notificatio` (reception).

## Fundamentum Ecosystematis (Foundation of the Ecosystem)

**Apriori** has no executable code — it is pure ontology, a type system.

Yet it is the foundation of the Umwelt ecosystem: every system that operates with
phenomena must interpret them through Apriori forms. Otherwise, chaos: no *Ding*
(thing) without *Form*, no *Actus* (act) without *Modus*.

Aussenwelt (external protocol) may vary — but it is always translated through
Apriori forms. As with Kant: although sensations vary, **a priori forms remain the same**.

## Dependentia Transcendentalis (Transcendental Dependence)

Why is Apriori the center?

Not because "everything depends on it" (technical causal dependence), but because
**everything is understood through it** (transcendental logical dependence).

Just as space is the condition of possibility for external vision, and time
the condition of possibility for internal experience — so Forma and Modus are
the conditions of possibility for systematic cognition.

A cogitative system without Apriori is not an imperfect system, but an *impossible* one:
no *cogitatio* (thinking) without categories through which thought is ordered.

## Installation

Package available in Hex. Add `apriori` to your dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:apriori, "~> 0.1.0"}
  ]
end
```

## Documentation

Full documentation available at [HexDocs](https://hexdocs.pm/apriori).

## Source

GitHub: [github.com/sovetnik/apriori](https://github.com/sovetnik/apriori)

## Vide Etiam (See Also)

- [Skull](https://github.com/sovetnik/skull) — MCP server framework using Apriori forms
- Kant, I. (1781). *Critique of Pure Reason* (*Kritik der reinen Vernunft*)