## Mathematicians Of The Day

### 24th July

On this day in 1985, Spain issued a 12 Spanish peseta stamp in honour of Esteban Terradas in their 'Famous People' series. See THIS LINK.

Click on for a poster.

#### Quotation of the day

##### From Émile Picard
In reality the origin of the notion of derivatives is in the vague feeling of the mobility of things, and of the greater or less speed with which phenomena take place; this is well expressed by the terms fluent and fluxion, which were used by Newton and which we may believe were borrowed from the ancient mathematician Heraclitus.