In Focus

Fermat’s “infinite descent” : In a letter to his friend Pierre de Carcavi, dated August 14, 1659, Pierre de Fermat (1601 – 1665) announces a method of mathematical proof, which he names “descent infinie ou indéfinie“…

The 15 puzzle in Arno Schmidt’s “Alexander”: In his novela “Alexander or What is Truth” (1949), Arno Schmidt discusses the question of historical truth about Alexander the Great (4th century B.C.). As usual in Schmidt’s works…

The Book of Birds : It is rather uncommon for a treatise in Mathematics to bear a title seemingly so irrelevant such as Abu Kamil’s “Book of Birds” (Kitab al-tair, 9th century). Abu Kamil (c. 850 – c. 930) was an ingenious…

A 9th century Indian variation of the “100 birds” problem : After an introductory salutation to Mahavira the god, the 24th omniscient teaching god of the Jains, his namesake Mahavira the teacher (9th century) introduces…