From The Guardian, by Tony Crilly

**Energetic historian of mathematics and logic**

When Ivor Grattan-Guinness, who has died aged 73 of heart failure, became interested in the history of mathematics in the 1960s, it was an area of study widely considered to be irrelevant to mathematics proper, or something that older mathematicians did on retirement. As an undergraduate at Oxford, he found that mathematics was presented drily, with no inkling of the original motivations behind its development. So Ivor set himself the task of asking “What happened in the past?” – as opposed, he said, to taking the heritage viewpoint of asking “How did we get here?”

Ivor Owen Grattan-Guinness, historian of mathematics and logic, born 23 June 1941; died 12 December 2014