19 / UX Laws

Occam’s Razor

When two approaches solve the same problem equally well, prefer the one that requires fewer assumptions.

Visual proof

The simplest adequate solution wins, not the solution with the fewest visible parts.

Story

A search flow adds tags, folders, saved views, and three filter modes before anyone has shown a need for them. A clear query and a useful result may solve the real problem. Simplicity begins with evidence, not with deleting at random.

Origin

The principle is associated with William of Ockham's preference for economy in explanation. The familiar name and later formulations have a more complicated history, which Thorburn examined in 1918.

Field Rules

  • 01

    Compare solutions against the same user need. Simpler is meaningful only when both approaches solve the important parts of the problem.

  • 02

    Question every step, field, mode, and setting. Keep it when it earns its cost through a real requirement or a demonstrated user need.

  • 03

    Do not move necessary complexity onto the user. A quiet screen can still hide a confusing process, vague defaults, or difficult recovery.

  • 04

    Prefer one coherent model over several overlapping ones. Fewer rules make the product easier to learn, explain, test, and maintain.

Examples

Digital systems

A focused search flow

The screen begins with a query and useful results. Filters appear when the result set needs refinement instead of asking every person to configure the search first.

Physical signals

One tool for one clear job

A well-shaped screwdriver may serve one task better than a multi-tool with many compromised attachments. Simplicity depends on the job, not the feature count alone.

Application

The solution has outrun the problem

Features and rules accumulate faster than evidence, so ordinary work becomes harder to learn and easier to break.

Resolves with
Keep the least complicated complete answer

Define the real need, compare credible approaches, and remove assumptions or features that do not improve the outcome.

Sources