Jyotish is a formal system before it is a reading. The classical texts state conditions and outcomes: this planet in that house, this lord with that strength, this yoga when these three things hold. purnika treats each such statement as a rule — a condition that can be tested against a chart, and an effect that follows when it holds.

The engine holds thousands of them, drawn from the classical texts of Jyotish, encoded one by one against the verse they come from. Nothing in the engine is invented; every rule can be traced back to its line.

A chart, then, is not read. It is run — the way a program is run — and what comes out is whatever the rules, taken together, have to say about it.

The texts are the source of truth. Where two of them disagree the engine keeps both, marks the disagreement, and lets the weighing decide — it does not pick a favourite and forget the other.

Rules do not act alone. A yoga is made by a strong lord, cancelled by a debilitated one, sharpened by an aspect, muted by a combustion. The engine runs them in layers: first the state of every planet — dignity, strength, house, aspects — then the rules that read those states, then the rules that read the rules.

Each layer feeds the next. What a rule can say about a chart depends on what the layers beneath it have already established, so a result is never a single match but a chain of conditions that all held at once.

The layers are ordered by dependency, not by tradition: a rule about a yoga cannot run until the strengths it depends on exist. The order is the architecture.

Because the layers are explicit, a result can be unfolded: which strength fed which rule, which rule fed which yoga, which yoga fed the sentence you are reading.

Most rules come with exceptions, and most exceptions with exceptions of their own. The texts are explicit about them; the engine keeps them explicit too. A filter is a rule that says when another rule does not apply, and filters run before effects are counted.

What survives the filters is weighed. Strength is a number, not a mood: shadbala, the position in the varga charts, the timing of the dasha. Two rules that disagree are settled by weight, and the weighing is written down with the result.

Nothing is rounded off to make the story cleaner. A weak yoga stays weak in the output; a cancelled one is shown cancelled, with the rule that cancelled it.

Timing is a filter too. A rule that holds in the chart may be silent for a decade and speak only when its dasha comes; the engine records when, not just whether.

The output is not a paragraph of prophecy. It is a structured picture: which rules fired, on what conditions, at what strength, and what they say. The prose is generated from that picture last, and every sentence in it points back to the rules that produced it.

This is what makes the engine an engine rather than an oracle. It can be checked. A rule can be argued with, corrected, re-run. The picture changes when the rules do, and the chart is the same chart it always was.

That is also why the engine can grow. A new verse becomes a new rule; a new rule joins its layer; the next run carries it — for every chart, at once.

And every run is reproducible: the same chart, the same rules, the same picture — today, next year, on any machine. That is the least a computation should promise.