After three years in the cavalry, during which time he became acquainted with fashionable social and mathematical circles, he moved to Paris and began building his reputation as a mathematician and literary wit.

Maupertuis, based on his exposition of Newton (with the help of his mentor Johan Bernoulli) predicted that the Earth should be oblate, while his rival Jacques Cassini measured it astronomically to be prolate.

In 1736 Maupertuis acted as chief of the French Geodesic Mission sent by King Louis XV to Lapland to measure the length of a degree of arc of the meridian.

In that work, Maupertuis proposed a theory of generation (i.e., reproduction) in which organic matter possessed a self-organizing “intelligence” that was analogous to the contemporary chemical concept of affinities, which was widely read and commented upon favourably by Georges-Louis Leclerc, Comte de Buffon.

He later developed his views on living things further in a more formal pseudonymous work that explored heredity, collecting evidence that confirmed the contributions of both sexes and treated variations as statistical phenomena.

Returning to Berlin in 1744, again at the desire of Frederick II, he was chosen president of the Royal Prussian Academy of Sciences in 1746, which he controlled with the help of Leonhard Euler until his death.

His position became extremely awkward with the outbreak of the Seven Years' War between his home country and his patron's, and his reputation suffered in both Paris and Berlin.

Finding his health declining, he retired in 1757 to the south of France with a young girl, leaving his wife and children behind and went in 1758 to Basel, where he died a year later.

[6] Maupertuis's difficult disposition involved him in constant quarrels, of which his controversies with Samuel König and Voltaire during the latter part of his life are examples.

[11] Bowler credits him with studies on heredity, with the natural origin of human races, and with the idea that forms of life may have changed with time.

Animals lacking a mouth could not live; others lacking reproductive organs could not perpetuate themselves; the only ones that remained are those in which order and fitness were found; and these species, which we see today, are but the smallest part of what blind destiny had produced.Mais ne pourroit-on pas dire, que dans la combinaison fortuite des productions de la Nature, comme il n'y avoit que celles où se trouvoient certains rapports de convenance, qui pussent subsister, il n'est pas merveilleux que cette convenance se trouve dans toutes les especes qui actuellement existent?

Le hasard, diroit-on, avoit produit une multitude innombrable d'Individus; un petit nombre se trouvoit construit de maniere que les parties de l'Animal pouvoient satisfaire à ses besoins; dans un autre infiniment plus grand, il n'y avoit ni convenance, ni ordre: tous ces derniers ont péri; des Animaux sans bouche ne pouvoient pas vivre, d'autres qui manquoient d'organes pour la génération ne pouvoient pas se perpétuer; les feuls qui soient restés, sont ceux où se trouvoient l'ordre & la convenance: & ces especes que nous voyons aujourd'hui, ne sont que la plus petite partie de ce qu'un destin aveugle avoit produit.

King-Hele (1963) points to similar, though not identical, ideas of thirty years later by David Hume in his Dialogues Concerning Natural Religion (1777).

In 1744, in another paper to the Paris Academy, he gave his Accord de plusieurs lois naturelles qui avaient paru jusqu'ici incompatibles (Agreement of several natural laws that had hitherto seemed to be incompatible) to show that the behaviour of light during refraction – when it bends on entering a new medium – was such that the total path it followed, from a point in the first medium to a point in the second, minimised a quantity which he again assimilated to action.

Today the concept of a ‘hard’ body is rejected; and mass times the square of velocity is just twice kinetic energy so modern mechanics reserves a major role for the inheritor quantity of ‘live force’.

Hence the principle of least action is not just the culmination of Maupertuis's work in several areas of physics, he sees it as his most important achievement in philosophy too, giving an incontrovertible proof of God.