Cauchy: Conviction, maths and politics | Tangente

A man of conviction

Cauchy's century was a veritable political laboratory: France passed through a succession of radically different regimes. Amid this constant change, Cauchy, a Legitimist, showed no lack of courage in defending his beliefs. Yet he remained steadfastly devoted to science, even when it meant helping regimes for which he had little sympathy.

Born under an absolute monarchy, Cauchy grew up under a constitutional monarchy, then lived through the First Republic and the First Empire. His youth unfolded during the Restoration, with the interlude of the Hundred Days. Unable to accept the fall of the Bourbons, he spent several years in exile before returning to France under the July Monarchy. He subsequently lived through the Second Republic and the Second Empire.

Throughout his life as a scholar, he was involved in the leading institutions of his day: École du Panthéon, lycée Napoléon, École polytechnique, École des ponts et chaussées, Académie des sciences, Collège de France, Bureau des longitudes and, finally, Faculté des sciences de Paris. Far from being ivory towers, these institutions were regularly affected by changes of regime, which continued to shape Cauchy's career long after he had established himself as one of the great mathematicians of his time.

The Bureau des longitudes episode ----------------------------------

His election to the Bureau des longitudes was a case in point. Unsurprisingly, in 1843 every member of the Bureau agreed that Cauchy's candidacy was the obvious choice. There was just one problem: he refused to swear allegiance to the king, though this was a legal requirement. At its meeting of 15 November, the Bureau acknowledged the situation while stating that "[i]t is not for the Bureau to investigate the reasons that have prevented the government from ruling on this appointment; but it is fulfilling a duty in assuring you, Mr Minister, that the present state of affairs cannot continue without causing real harm to astronomy." Would Cauchy's expertise save him? Two weeks after making this request, the Bureau des longitudes received a flat refusal from the Minister of Public Instruction.

Nevertheless, Cauchy was so keen to take part in the Bureau's work that he forced his way in. At the meeting of 1^st March 1848, the following strange incident occurred: "Before the meeting had opened, Mr Cauchy entered the meeting room without notifying anyone and signed the attendance sheet. Since Mr Cauchy was not a member of the Bureau des longitudes, the chair asked him to leave and, with the unanimous approval of the Bureau, struck his name from the attendance sheet." The closing of this door at the Bureau des longitudes affected Cauchy's scientific output: he was forced to set aside his research in astronomy, the Bureau's chosen field.