State your purpose in one sentence before writing — the purpose selects the right abstraction level
Before beginning any communication, writing, or presentation, state in one sentence what you are trying to accomplish, then use that purpose statement to select the appropriate level of abstraction.
Why This Is a Rule
Abstraction level mismatches are the most common cause of communication failure: you deliver a strategic overview when the audience needs implementation details, or you dive into technical specifics when the audience needs the high-level rationale. The mismatch happens because the abstraction level was chosen based on what's comfortable for the writer rather than what serves the purpose.
A one-sentence purpose statement ("I am trying to get the team aligned on the migration timeline") determines the correct abstraction level: timeline-level detail, not code-level or strategy-level. "I am trying to convince the VP to fund this project" determines a different level: business outcomes and ROI, not implementation specifics.
The purpose must be stated before writing begins because once you start writing, the level of abstraction self-selects based on what you know best — which is usually too detailed (you're an expert) or too abstract (you're uncertain). The purpose statement overrides the self-selection with intent-driven selection.
When This Fires
- Before writing any email, document, presentation, or message
- Before starting any meeting or conversation with a specific objective
- When a draft feels "off" but you can't identify why (often a level-of-abstraction mismatch)
- Before any communication where the audience's needs differ from your default level
Common Failure Mode
Starting to write without stating the purpose, then discovering mid-draft that you're at the wrong abstraction level. You've written 500 words of technical detail for an audience that needs a 3-sentence executive summary. The purpose statement catches this at word zero, not word 500.
The Protocol
Before any communication: (1) Write one sentence: "I am trying to [specific objective] for [specific audience]." (2) Use the purpose to select abstraction level: does the audience need strategic direction? Operational plan? Technical detail? (3) Constrain the communication to that level. Resist the pull toward your default level. (4) If the communication requires multiple levels (common in longer documents), sequence them: purpose-matched level first, supporting detail second.