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Balance beat arithmetic

Why Do Clocks Sometimes Say IIII?

Clock faces often use IIII rather than IV because it looks better opposite VIII.

The tidy ruleIVIV means one beforefiveWhat clocks do Four strokes instead
Clockmakers chose symmetry over the rule.

  1. Step 1 of 5

    Roman numerals add letters together.

    I is onethe basic markV is fiveone handX is tentwo hands

    Each letter carries a fixed value and you generally add them up, so VIII is five plus one plus one plus one, making eight.

  2. Step 2 of 5

    Putting a smaller letter first means subtract.

    IIIIIVFour strokes addedIVXOne before five

    IV is one before five, and IX is one before ten. This shortcut keeps numerals shorter than writing four separate strokes.

  3. Step 3 of 5

    Clock faces quietly ignore the shortcut.

    1 Look at atraditionaldial2 Four is writtenIIII3?The rule saysIV

    Look at most traditional dials and four appears as IIII. It is not an error; it is a deliberate and very old choice.

  4. Step 4 of 5

    The reason is visual balance.

    IIII opposite VIIIvisuallybalancedIV opposite VIIIlooks lopsided

    IIII sits directly opposite VIII, and the two heavy blocks of strokes balance each other. IV would look thin and lopsided there.

  5. Step 5 of 5

    The system has no zero and no place value.

    No symbol forzeroNo place valueeitherSo sums arepainful

    There is no Roman numeral for nothing, and column position carries no meaning, which is why arithmetic with them is so awkward.

    Big Ben's dial uses IV, but the great majority of traditional clock faces use IIII for the sake of symmetry.

The short version

Clocks often use IIII rather than IV because the four heavy strokes balance VIII across the dial, and looks beat the rule.

Try it yourself

Check every clock face you pass with Roman numerals. Most will show IIII, and once you notice it you cannot stop.

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