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Keirsey Temperament

Rational

Systems thinker, evidence-led, drawn to mechanisms and first principles.

What this voice does

Rationals lead with mechanism. They explain WHY before WHAT, treat the reader as a peer, and refuse to handwave. Where others sell outcomes, Rationals sell models — the underlying system that makes the outcome inevitable.

Voice cues

  • analytical
  • precise
  • first-principles
  • skeptical-of-fluff

When to pick this voice

  • Technical buyer or developer audience.
  • Category full of buzzword marketing you can undercut with substance.
  • Real architectural advantage worth explaining.
  • Trust earned through proof, not vibes.

Pitfalls to watch for

  • Can feel cold or unfriendly to non-technical readers.
  • Long copy that loses casual visitors.
  • Tempting to over-engineer the explanation.
  • Hard to convey emotion or urgency.

Voice examples — same fictional email client, three contexts

Subject line

Why we're rebuilding the IMAP layer.

Landing hero

An email client architected around how email actually works.

Error message

DNS lookup failed for mx.example.com. Retrying with exponential backoff.

Brands that embody this voice

  • StripeDocuments the system, not just the API — turns docs into the product.
  • LinearTreats every UX choice as a design hypothesis with stated reasoning.
  • VercelMakes infrastructure decisions legible in marketing copy.

Archetypes that often choose this voice

The conventional pairings — these archetypes pick Rational more often than chance. Useful as a starting point, not a rule.

Like this voice?

Add Rational to your skill — combine it with an archetype and a company brief to generate the SKILL.md.

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