Physicists 18th century
Bernard Bolzano, full name Bernard Placidus Johann Nepomuk Bolzano, was an Italian-born Czech scientist, mathematician, logician, philosopher and theologian.
Bolzano graduated from the University of Prague and was immediately appointed professor of philosophy and religion at the university. Within a few years, however, Bolzano had already shown himself to be a free thinker with his teachings on the social costs of militarism and the needlessness of war. He called for a complete reform of the educational, social, and economic systems that would direct the nation's interests toward peace rather than armed conflict between states. In 1819, Bolzano was expelled from the university for his beliefs and thereafter turned his full attention to works on social, religious, philosophical, and mathematical issues.
Bolzano held advanced views on logic, mathematical quantities, limits, and continuity. He is the author of the first rigorous theory of real numbers and one of the founders of set theory. In his studies of the physical aspects of force, space, and time, he proposed theories opposed to those advanced by the German philosopher Immanuel Kant. His contributions to logic, in particular, established his reputation as the greatest logician of his time. Much of his work remained unpublished during his lifetime and was not widely disseminated until the late nineteenth and early twentieth centuries, when a number of his conclusions were reached independently.
Bolzano was multi-talented in various fields of science to which he made significant contributions. His published works include The Binomial Theorem (1816), A Purely Analytic Proof (1817), The Functional Model and the Scientific Model (1834), An Attempt at a New Statement of Logic (1837), and The Paradoxes of Infinity (1851).
Among other things, Bolzano was also a great philanthropist. Together with his friends and students, he supported the activities of almshouses, homes for the blind, loan banks for the working class, libraries, and elementary schools in rural areas.
Mathurin Jacques Brisson was a French zoologist, ornithologist, naturalist and physicist, a member of the Academy of Sciences.
He is known for his published works in natural history: Le Règne animal ("The Kingdom of Animals", 1756) and Ornithologie ("Ornithology", 1760), in which he described 1,500 species of birds grouped into 115 genera, twenty-six orders, and two classes. Brisson was one of the first to come close to the concept of "type" in zoology, although he does not use the term, but his classification was used for about 100 years. He translated a number of important books on zoology for his time into French.
Brisson's works in physics are related to the measurement of specific gravity of various bodies, the study of gases and refraction of light, mirrors, magnetism, atmospheric electricity, and barometers.
John Dalton was a British scientist, chemist and physicist, naturalist, and pioneer in the development of modern atomic theory.
In the 1800s, he was the first scientist to explain the behavior of atoms in terms of weight measurements. Some of the tenets of Dalton's atomic theory proved to be false, but most of the conclusions remain valid to this day.
Problems with his own eyesight led Dalton to research and describe the visual defect he himself suffered from in 1794 - color blindness, later named color blindness in his honor.
Leonhard Euler was the greatest mathematician of the 18th century and history in general.
Euler brilliantly graduated from the University of Basel and entered the St. Petersburg Academy of Sciences, then began to work at the Berlin Academy, and later to lead it. In 1766, the scientist received an invitation from the Russian Empress Catherine II and again came to St. Petersburg to continue his scientific work.
Here he published about 470 works in a wide variety of fields. One of them is a large-scale work "Mechanics" - an in-depth study of this science, including celestial mechanics. Euler by that time was practically blind, but continued to be actively engaged in science, in the records he was helped by his son Johann Albrecht and stenographers. Leonhard Euler made many fundamental discoveries that brought great benefit to mankind.
His massive contribution to the development of mathematics, mechanics, physics and astronomy cannot be overestimated, and his knowledge in the most diverse branches of science is admirable. During his lifetime, he published more than 850 works that contain in-depth studies of botany, chemistry, medicine, ancient languages, and music. Euler held membership in many academies of science around the world.
Joseph Fourier, full name Jean-Baptiste Joseph Fourier, was a French mathematician and physicist and historical Egyptologist.
Fourier famously accompanied Napoleon Bonaparte on his Egyptian expedition in 1798 as a scientific advisor and was appointed secretary of the Institute of Egypt. During the occupation of Egypt, Fourier worked in the French administration, supervised archaeological excavations, and worked to shape the educational system.
But the main thing in Fourier's life was science. Back in France, he studied the mathematical theory of heat conduction, established the partial differential equation governing heat diffusion, and solved it using an infinite series of trigonometric functions. Fourier showed that heat diffusion obeyed simple observable physical constants that could be expressed mathematically. His work The Analytic Theory of Heat (1822) had a great influence on the development of physics and pure mathematics.
Joseph Fourier was a member of the Paris Academy of Sciences, the French Academy, a foreign honorary member of the St. Petersburg Academy of Sciences, and a member of the Royal Society of London.
Gottfried Wilhelm Leibniz was a German philosopher and a prominent polymath in many fields of science.
Leibniz was a universal genius; he showed his talents in logic, mathematics, mechanics, physics, law, history, diplomacy, and linguistics, and in each of the disciplines he has serious scientific achievements. As a philosopher, he was a leading exponent of 17th-century rationalism and idealism.
Leibniz was a tireless worker and the greatest scholar of his time. In the fate of Leibniz, among other things, there is one interesting page: in 1697, he accidentally met the Russian Tsar Peter I during his trip to Europe. Their further meetings led to the realization of several grandiose projects in Russia, one of which was the establishment of the Academy of Sciences in St. Petersburg.
Gottfried Wilhelm Leibniz was also the founder and first president of the Berlin Academy of Sciences and a member of the Royal Society of London.
Isaac Newton was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the greatest mathematicians and physicists and among the most influential scientists of all time. He was a key figure in the philosophical revolution known as the Enlightenment. His book Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus.
In the Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for tides, the trajectories of comets, the precession of the equinoxes and other phenomena, eradicating doubt about the Solar System's heliocentricity. He demonstrated that the motion of objects on Earth and celestial bodies could be accounted for by the same principles. Newton's inference that the Earth is an oblate spheroid was later confirmed by the geodetic measurements of Maupertuis, La Condamine, and others, convincing most European scientists of the superiority of Newtonian mechanics over earlier systems.
Giovanni Vincenzo Petrini was an Italian priest and theologian, philosopher, mathematician, and expert in mineralogy.
Along with Scipio Breislacus, Petrini was one of the founders of Italian volcanology. He taught philosophy and mathematics, theology, but specialized in mineralogy and created the Mineralogical Cabinet in Nazareth. This museum was famous in Europe and was visited, among others, by Emperor Joseph II, who gave him rare specimens from the lands of the Empire and especially from Hungary.
Giovanni Petrini was the author of the catalog Gabinetto mineralogico del Collegio Nazareno ("The Mineralogical Cabinet of the Nazarene Collegium, described by external features and distributed by component parts" (Rome, 1791-1792). The specimens in it are classified according to a standard structure: salts, earths, bitumens, combustibles, and metals. There is also a section on gemstones.
