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Comment by Xmd5a

The meter wasn't invented during the French Revolution, it evolved from ancient measurement systems based on the golden ratio.

Traditional body measurements (thumb, palm, span, foot, cubit) follow a Fibonacci-like progression where each unit ≈ φ times the previous one. If we consider the Egyptian cubit as π/6 meters (which matches historical measurements), here's a possible insight:

Draw a circle with diameter 1 meter. Remove 1/6 of the perimeter (π/6), subtract the diameter (1), and you get ≈1.618 – essentially φ. This geometric construction lets you build an entire measurement system using just a stick and basic geometry. Once you have any two consecutive units, you can generate the entire sequence by addition (palm + span = foot) or subtraction (span – palm = thumb's breadth).

In the pre-metric French system, a span was exactly 20cm. When you scale 0.2 × φ² you get π/6 with 4-digit precision. But here's what's interesting: using our geometric approximation φ ≈ 5π/6 – 1, the equation 0.2 × φ² = π/6 works out *exactly*. The "approximation error" in φ perfectly cancels out due to φ² = φ + 1, making 0.2 × (5π/6 - 1 + 1) = π/6.

Here's another "coincidence": Multiple 17th-century scientists (Mersenne, Huygens, Wilkins) proposed defining a universal unit as the length of a pendulum with a half-period of 1 second. Tito Livio Burattini, inspired by his travels in Egypt, formalized this in his "Misura Universale" (1675), measuring this pendulum length at 0.9939 meters - essentially our modern meter.

The "revolutionary" meter system was really just formalizing measurement relationships that builders had been using for millennia. The French didn't invent it - they just gave ancient φ-based measurements a decimal makeover.

parent Xmd5a 1 year ago

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