On =, +, – and many Z’s.

May 29, 2009

Robert Recorde

Robert Recorde is as famous for being a Welshman who actually invented something useful, as he is for his invention. His greatest gift appears to have been the equals sign:

…to avoid the tedious repetition of these words: “is equal to”, I will set (as I do often in work use) a pair of parallels of one length (thus =), because no two things can be more equal.


As if this wasn’t enough, he may also have introduced the plus and minus signs to the UK:

There be other 2 signes in often use of which the first is made thus + and betokeneth more: the other is thus made – and betokeneth lesse


Great these achievements may be, but his finest idea unfortunately didn’t catch-on, which was to name the eighth power of a number it’s… zenzizenzizenzic.

Leave a Reply