scientific-prose-style

scientific-prose-style

Rules for the prose of a scientific paper — the sentences of the abstract, introduction, results, and discussion. Load this whenever you draft or revise manuscript text. (Figure planning lives in figure-planner; this skill is about words on the page.)

Rule 1 — Em-dash budget (the headline rule)

The long em-dash (—) is the single most overused mark in generated scientific prose. It feels punchy in isolation but a reader hits three or four per paragraph and it reads as a stylistic tic, not as writing. Cap it.

• At most one em-dash per paragraph, and none in the abstract. If a sentence already has one, the next clause that wants a dash gets a different mark.
• Never use a pair of em-dashes to bracket an aside if a comma pair or parentheses would do — the double dash is the worst offender.
• Prefer, in rough order: comma (mild pause), colon (a list or an expansion of what precedes), parentheses (a true aside the sentence reads fine without), or split into two sentences (the strongest fix for a long dash-spliced line).

Substitution table

Before → after (from a real over-dashed abstract)

Before (5 em-dashes, tic-heavy):

Starting from the hardest instance of the problem — allele-resolution prediction, distinguishing many coding variants of the same gene — we assemble a benchmark, and find this is a measurement limit, not a model limit — a split-half floor shows the distance is no larger than sampling noise.

After (0 em-dashes, same content):

We start from the hardest instance of the problem: allele-resolution prediction, which distinguishes many coding variants of the same gene. On the benchmark we assemble, the ceiling turns out to be a measurement limit rather than a model limit. A split-half floor analysis shows the perturbation-versus- control distance is no larger than the sampling noise between two halves of a variant's own cells.

Note what the rewrite does: promotes one clause to its own sentence, turns the bracketed aside into a relative clause, and swaps the contrast dash for "rather than." The prose is calmer and each sentence carries one idea.

Rule 2 — Don't trade the dash for a colon tic

Colons are the natural replacement, but the same overuse applies: at most one colon per sentence, and if every sentence in a paragraph ends ...: <expansion> you've just moved the tic. Vary the repair — some become periods, some commas.

Rule 3 — Hedge once, not thrice

Scientific prose stacks hedges (may possibly suggest that ... could in principle ...). State the claim with one qualifier and the confidence level, then stop. These results suggest X — not These results may tentatively be taken to suggest that X could hold.

Rule 4 — Vary sentence length; one idea per sentence

A paragraph of uniformly long, clause-heavy sentences is as fatiguing as the dash tic. Follow a long sentence with a short one. If a sentence has three clauses joined by dashes, semicolons, and "and," it is three sentences.

Rule 5 — Openers and connectives

• Don't open consecutive paragraphs with the same word (We ... We ... We ...).
• Prefer plain connectives (but, so, because, here) over heavy ones (moreover, furthermore, additionally) unless enumerating.

Self-check before you hand prose back

Run this on any abstract/intro/section you write:

1. Count em-dashes. More than one per paragraph, or any in the abstract → rewrite the excess with the substitution table.
2. Count paragraph-opening words. Repeated opener → vary it.
3. Read the longest sentence aloud. If you run out of breath, split it.
4. En-dashes in numeric ranges (5–10) and hyphens in compounds (single-cell) are fine and are not counted against the budget.

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Provenance: adapted from the Claude Science scientific-prose-style skill (Apache-2.0). Cross-references to figure skills were repointed to this repo's figure-planner.