Robert Recorde

Two equal things, joined by $=$ .

A short story

A Welsh teacher who wanted maths to be friendlier. In his book The Whetstone of Witte he was tired of writing is equal to over and over, so he invented a short mark for it: two parallel lines, the same length, side by side. He picked them, he wrote, because no two things could be more equal.

In their own words

No two things can be more equal than a pair of parallels of one length.

Paraphrased: from Recorde, The Whetstone of Witte, 1557.

The lab their idea turned into

Balance Lab

Keep both sides fair to set the unknown free.

Open Balance Lab →