Julien Offroy de La Mettrie – Physician and Philosopher

Physician and Philosopher

He was born on Decmeber 25, 1709, in Saint-Malo, France and died on November 11, 1751, in Berlin.  He is a physician and philosopher whose Materialistic interpretation of psychic phenomena laid the groundwork for future developments of behaviorism and played an important part in the history of modern Materialism.  He obtained a medical degree at Reims, studied medicine in Leiden under Herman Boerhaave (some of whose works he translated into French), and served as surgeon to the French military.  A personal illness convinced him that psychic phenomena were directly related to organic changes in the brain and nervous system.  The outcry following publication of these views in Histoire naturelle de l’ame (1745; “Natural History of the Soul”) forced his departure from Paris.  The book was burned by the public hangman.  In Holland La Mettrie published L’Homme-machine (1747; L’Homme Machine: A Study in the Origins of an Ida, 1960), developing more boldly and completely, and with great originality, his materialistic and atheistic views.  The ethics of these principles were worked out in Discours sur le Bonheur ou l’ anti-Seneque (“Discourse on Happiness, or the Anti-Seneca”).  He was then forced to leave Holland but the Great, made court reader, and appointed to the academy of science.  In accord with his belief that atheism was the sole road to happiness and sense pleasure the purpose of life (Le Petit Homme a longue quequ, 1751; “The Small Man in a Long Queuq”), he was a carefree hedonist to the end, finally dying of ptomaine poisoning.  His collected works, Oeuvres philosophiques, were published in 1751, and selections were edited by Marcelle Tisserand in 1954.

Photo courtesy:  answer

Johann Heinrich Lambert

Johann Heinrich Lambert

Johann Heinrich Lambert was born on August 26, 1728 at Mulhausen, Alsace, now Mulhouse, France.  He died on September 25, 1777 at Berlin.  Swiss-German mathematician, astronomer, physicist, and philosopher who provided the first rigorous  proof than π (the ration  of a circle’s circumference to its diameter) is irrational, meaning it cannot be expressed as the quotient of two integers.

The son of tailor, Lambert was largely self-educated and early began geometric and astronomical investigations by means of instruments he designed and built himself.  He worked for a time as a bookkeeper, secretary and editor.  As a private tutor in 1748, he gained access to a good library, which he utilized for self-improvement until 1759, when he resigned to settle in Augsburg.  In 1764 he went to Berlin, where he received the patronage of Frederick the Great.  His memoir containing the proof that π is irrational was published in 1768.  In 1774 at ‘Berlin, he became editor of Astronomisches Jahrbuch oder Ephemeriden, an astronomical almanac.

Lambert made the first systematic development of hyperbolic functions.  He is also responsible for many innovations in the study of heat and light.  The lambert, a measurement of light intensity, was named in his honour.  Among his most important works are Photometria (1760), Die Theorie der Parallellinien (1766; “The Theory of Parallel Lines”), and Pyrometrie (1779).  The Neues Organon (1764; “New Organon”), his principal philosophical work, contains and analysis of a great variety of questions, among them formal logic, probability, and the principles of science.

Niels Henrik Abel (2 of 3)

While waiting for the royal decree to be issued, in 1824 the published at his own expense his proof of the impossibility of solving algebraically the general equation of the fifth degree, which he hoped would bring him recognition.  He sent the pamphlet to Gauss, who dismissed it, failing to recognize that the famous problem had indeed been settled.

Abel spent the winter of 1825-26 with Norwegian friends in Berlin, where he met August Leopold Crelle, civil engineer and self-taught enthusiast of mathematics, who became his close friend and mentor.  With Abel’s warm encouragement, Crelle founded the Journal fűr die reine und angewandte Mathematik (“Journal for Pure and Applied Mathematics”), the first volume of which (1826) contains papers by Abel, including a more elaborate version of his work on the quintic equation.  Other papers dealt with equation theory, functional equations, integration in finite forms, and problems from theoretical mechanics.

Abel’s early mathematical training had been in the formal school typified by Euler.  In Berlin new directions in mathematics stimulated him to do further independent work.  Soon distracted socially, however, Abel travelled throughout Europe.

Arriving in Paris in the summer of 1826, he called on the foremost mathematicians and completed a memoir on transcendental functions.  In this major work he presented a theory of integrals of algebraic functions, in particular the result know as Abel’s theorem: there is a finite number, or genus, of independent integrals of this nature.