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"A polymath (Greek: πολυμαθής, polymathēs, "having learned much") is a person whose expertise spans a significant number of different subject areas; such a person is known to draw on complex bodies of knowledge to solve specific problems. The term was first used in the seventeenth century but the related term, polyhistor, is an ancient term with similar meaning.
"The term is often used to describe those great thinkers of the Renaissance and the Enlightenment, each of whom excelled at several fields in science and the arts, including such individuals as Leonardo da Vinci, Michelangelo, Hildegard von Bingen, Gottfried Wilhelm Leibniz, Galileo Galilei, Benjamin Franklin, Rabindranath Tagore, Paolo Sarpi, Nicolaus Copernicus, Francis Bacon, Walter Russell, Thomas Browne, Jose Rizal, Michael Servetus, Ibn al-Haytham, and Omar Khayyám.
"In Renaissance Italy, the idea of the polymath was expressed by one of its most accomplished representatives, Leon Battista Alberti (1404–1472), in the statement that "a man can do all things if he will." Embodying a basic tenet of Renaissance humanism that humans are limitless in their capacity for development, the concept led to the notion that people should embrace all knowledge and develop their capacities as fully as possible. This was expressed in the term "Renaissance man" which is often applied to the gifted people of that age who sought to develop their abilities in all areas of accomplishment: intellectual, artistic, social and physical. This term entered the lexicon during the twentieth century and has now been applied to great thinkers living before and after the Renaissance.
"Many notable polymaths lived during the Renaissance period, a cultural movement that spanned roughly the 14th through to the 17th century and that began in Italy in the late Middle Ages and later spread to the rest of Europe. These polymaths had a rounded approach to education that reflected the ideals of the humanists of the time. A gentleman or courtier of that era was expected to speak several languages, play a musical instrument, write poetry, and so on, thus fulfilling the Renaissance ideal. The idea of a universal education was essential to achieving polymath ability, hence the word university was used to describe a seat of learning. At this time universities did not specialize in specific areas but rather trained students in a broad array of science, philosophy, and theology. This universal education gave them a grounding from which they could continue into apprenticeship toward becoming a Master of a specific field. During the Renaissance, Baldassare Castiglione, in his guide The Book of the Courtier, described how an ideal courtier should have polymathic traits.
"'A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects."
"Robert A. Heinlein, Time Enough for Love (1973)
"Castiglione's guide stressed the kind of attitude that should accompany the many talents of a polymath, an attitude he called sprezzatura. A courtier should have a detached, cool, nonchalant attitude, and speak well, sing, recite poetry, have proper bearing, be athletic, know the humanities and classics, paint and draw and possess many other skills, always without showy or boastful behavior, in short, with "sprezzatura". The many talents of the polymath should appear to others to be performed without effort, in an unstrained way, almost without thought. In some ways, the gentlemanly requirements of Castiglione recall the Chinese sage, Confucius, who far earlier depicted the courtly behavior, piety and obligations of service required of a gentleman. The easy facility in difficult tasks also resembles the effortlessness inculcated by Zen, such as in archery where no conscious attention, but pure spontaneity, produces better and more noble skill. For Castiglione, the attitude of apparent effortlessness should accompany great skill in many separate fields. In word or deed the courtier should "avoid affectation ... (and) ... practice ... a certain sprezzatura ... conceal all art and make whatever is done or said appear to be without effort and almost without any thought about it"
"This Renaissance ideal differed slightly from the "polymath" in that it involved more than just intellectual advancement. Historically (roughly 1450–1600) it represented a person who endeavored to "develop his capacities as fully as possible" (Britannica, "Renaissance Man") both mentally and physically, and, as Castiglione suggests, without "affectation".
"A different term for polymath is Renaissance man, which was first recorded in written English in the early 20th century. Other similar terms in use are Homo Universalis (Latin) and Uomo Universale (Italian), which translate to "universal person" or "universal man". When someone is called a "Renaissance man" or "Renaissance woman" today, it is meant that, rather than simply having broad interests or superficial knowledge in several fields, he or she possesses a more profound knowledge and a proficiency, or even an expertise, in at least some of those fields. The related term generalist – contrasted with a specialist – is used to describe a person with a general approach to knowledge. Today, the expression "Renaissance man" is usually used to describe a person with intellectual or scholastic proficiency and not necessarily the more universal learning implied by Renaissance humanism. Some dictionaries use the term "Renaissance man" to describe someone with many interests or talents, while others give a meaning restricted to the Renaissance and more closely related to Renaissance ideals.
"The term Universal Genius is also used, with Leonardo da Vinci as the prime example again. The term seems to be used especially when a person has made lasting contributions in at least one of the fields in which he was actively involved, and when he had a universality of approach.
"When a person is described as having encyclopedic knowledge, he or she exhibits a vast scope of knowledge. This designation may be anachronistic, however, in the case of persons such as Eratosthenes whose reputation for having encyclopedic knowledge pre-dates the existence of any encyclopedic object."