AI started to shift paradigms, from symbolism to connectionism, from defining (and programming) every aspect of learning and thinking, to statistical inference or finding connections or correlations leading to learning based on observations or experience.

Llull’s system was based on the belief that only a limited number of undeniable truths exists in all fields of knowledge and by studying all combinations of these elementary truths, humankind could attain the ultimate truth. His art could be used to “banish all erroneous opinions” and to arrive at “true intellectual certitude removed from any doubt.”

In the 17th century, his works Ars magna and Ars brevis gained greater influence through the system of a perfect philosophical, universal language described therein. This system is based on a combination of philosophical basic concepts. Llull’s thoughts were taken up by Gottfried Wilhelm LeibnizGottfried Wilhelm LeibnizGottfried Wilhelm von Leibniz (German: [ˈɡɔtfʁiːt ˈvɪlhɛlm fɔn ˈlaɪbnɪts] or [ˈlaɪpnɪts]) (July 1, 1646 – November 14, 1716) was a German mathematician and philosopher. He occupies a prominent place in the history of mathematics and the history of philosophy.Leibniz developed the infinitesimal calculus independently of Isaac Newton, and Leibniz's mathematical notation has been widely used ever since it was published. It was only in the 20th century that his Law of Continuity and Transcendental Law of Homogeneity found mathematical implementation (by means of non-standard analysis). He became one of the most prolific inventors in the field of mechanical calculators. While working on adding automatic multiplication and division to Pascal's calculator, he was the first to describe a pinwheel calculator in 1685 and invented the Leibniz wheel, used in the arithmometer, the first mass-produced mechanical calculator. He also refined the binary number system, which is at the foundation of virtually all digital computers.In philosophy, Leibniz is most noted for his optimism, e.g., his conclusion that our Universe is, in a restricted sense, the best possible one that God could have created. Leibniz, along with René Descartes and Baruch Spinoza, was one of the three great 17th century advocates of rationalism. The work of Leibniz anticipated modern logic and analytic philosophy, but his philosophy also looks back to the scholastic tradition, in which conclusions are produced by applying reason to first principles or prior definitions rather than to empirical evidence.Leibniz made major contributions to physics and technology, and anticipated notions that surfaced much later in philosophy, probability theory, biology, medicine, geology, psychology, linguistics, and computer science. He wrote works on philosophy, politics, law, ethics, theology, history, and philology. Leibniz's contributions to this vast array of subjects were scattered in various learned journals, in tens of thousands of letters, and in unpublished manuscripts. He wrote in several languages, but primarily in Latin, French, and German. There is no complete gathering of the writings of Leibniz.birth year1646death year1716era18th-century philosophyeraAge of Enlightenmentis influenced by ofAlfred North Whiteheadinfluenced byAristotle, the founder of mathematical logic. In the 19th century William Stanley JevonsWilliam Stanley JevonsWilliam Stanley Jevons, LL.D., M.A., F.R.S. (/ˈdʒɛvənz/;1 September 1835 – 13 August 1882) was an English economist and logician.Irving Fisher described Jevons' book A General Mathematical Theory of Political Economy (1862) as the start of the mathematical method in economics. It made the case that economics as a science concerned with quantities is necessarily mathematical. In so doing, it expounded upon the "final" (marginal) utility theory of value. Jevons' work, along with similar discoveries made by Carl Menger in Vienna (1871) and by Léon Walras in Switzerland (1874), marked the opening of a new period in the history of economic thought. Jevons' contribution to the marginal revolution in economics in the late 19th century established his reputation as a leading political economist and logician of the time.Jevons broke off his studies of the natural sciences in London in 1854 to work as an assayer in Sydney, where he acquired an interest in political economy. Returning to the UK in 1859, he published General Mathematical Theory of Political Economy in 1862, outlining the marginal utility theory of value, and A Serious Fall in the Value of Gold in 1863. For Jevons, the utility or value to a consumer of an additional unit of a product is inversely related to the number of units of that product he already owns, at least beyond some critical quantity.It was for The Coal Question (1865), in which he called attention to the gradual exhaustion of the UK's coal supplies, that he received public recognition, in which he put forth what is now known as Jevon's paradox, i.e. that increases in energy production efficiency leads to more not less consumption. The most important of his works on logic and scientific methods is his Principles of Science (1874), as well as The Theory of Political Economy (1871) and The State in Relation to Labour (1882). Among his inventions was the logic piano, a mechanical computer.birth year1835death year1882influencedAlfred Marshallis notable student ofAugustus De Morgandeath placeBexhill-on-SeafieldEconomics tried to realize the idea of a logical machine. Llull studied both syllogism and induction. He was the first to devote himself to the systematic study of material implication, which is one of the fundamental operations of mathematical logic, analyzing logical operations with the copula “and” (conjunction) and the copula “or” (disjunction).