Niccolò Machiavelli, 1469–1527. Renaissance Italian thinker often viewed as the first political scientist. Machiavelli studied political and military history with a view to practical applications. The Prince is his most famous work.

From the short bio at Duke University: Alasdair MacIntyre [Emeritus after 1999-2000] has taught at several universities in England before emigrating in 1970. Since then he has taught at Brandeis University, Boston University, Wellesley College, Vanderbilt University and the University of Notre Dame. In 1989 he was a Luce Visiting Scholar at the Whitney Humanities Center of Yale University. His books include: A Short History of Ethics, After Virtue. Whose Justice? Which Rationality? and Three Rival Versions of Moral Enquiry. His central interests are in the history of ethics, and more especially in the moral philosophies of Aristotle and Aquinas, and in the nature of practical rationality. He is a past President of the Eastern Division of the American Philosophical Association. His work has been very influential in ethics, and the recent revival of interest in virtue theory owes a lot to him.

Catharine Alice MacKinnon, b. 1946. American lawyer, legal theorist, political philosopher and feminist thinker.

Salomon Maimon (1753-1800), German Enlightenment philosopher of the 18th century, contemporary and critic of Kant.

Moses Maimonides (Moses ben Maimon, Rambam), 1135-1204. Medieval Jewish philosopher and Talmudic scholar. His Aristotelian teachings were influential with both Islamic and Christian medieval scholars, most notably Aquinas.

French philosopher

Nicholas Malebranche (1638-1715), French Cartesian philosopher.

Ernst Mally (1879-1944), Austrian philosopher and student of Alexius Meinong.

University Research Chair in Relational Art and Philosophy at Concordia University, known for her exploration of the senses and arts

Herbert Marcuse, 1898-1979. German-born philosopher who spent much of his productive career in the United States. Prominent member of the Frankfurt School.

Caesar Marcus Aurelius Antoninus Augustus (121-180 A.D.), Roman Emperor known for scholarly works and wars fought under his reign.

Jacques Maritain, 1882-1973. French Catholic philosopher, the leading 20th-century interpreter of Aquinas. His primary legacy is in moral and political philosophy, and he was a co-author of the 1948 Universal Declaration of Human Rights.

Dora Marsden, 1882-1960. Twentieth-century British philosopher and author, identified with Egoism and anarcha-feminism.

Marsilius of Inghen, c. 1330 - 1396. Medieval Dutch philosopher and theologian. He was a pupil of Buridan.

Lady Damaris Cudworth Masham, 1659-1708. Early Modern English philosopher. She was the daughter of Platonist Ralph Cudworth, and a very close friend of John Locke. Her own writings center on ethics.

Canadian political philosopher and social theorist known for his focus on perception, affect and the virtual.

John Henry McDowell (born 1942), a philosopher who has written extensively on metaphysics, epistemology, ancient philosophy, and meta-ethics. His most influential work has been in the philosophy of mind and language.

John McTaggart Ellis McTaggart, 1866-1925. A leading British Idealist who was long obsessed by Hegel's logic, but eventually got over it. His philosophical work centered on metaphysics.

George Herbert Mead, 1863-1931. An American reformer and philosopher of the Chicago school of pragmatism. His principal influence has been on the philosophy of the social sciences, especially sociology, where he introduced the theory of symbolic interaction.

Alexius Meinong, 1853-1920. Austrian philosopher who forced Russell, Wittgenstein, and Ryle to realize that meanings are not objects.

Melissos (or Melissus) of Samos. fl. mid-5th century BC. Early Greek thinker generally counted among the Eleatic school. His thought comes to us only in a handful of fragments and secondhand accounts.

Mencius (Meng Tzu, Meng Xi), c. 371 BC - c. 286 BC. Classical Chinese sage who is a key influence in Confucianism and Chinese thought generally. Known for his teaching of the goodness of human nature.

Moses Mendelsohn, 1729-1786. Eighteenth-century German Jewish philosopher. He was most active in the philosophy of religion, having been a Talmudic scholar before entering mainstream philosophy.

Menippus (Menippos) of Gadara, fl. c. 250 BC. Ancient Cynic philosopher and satirist. His satires, now lost, are said to have inspired the much later writings of Lucian and Varro.

Maurice Merleau-Ponty, 1908-1961. French phenomenologist influenced by Husserl and generally associated with existentialism.

Marin Mersenne, 1588-1648. Early Modern French priest and philosopher. He corresponded widely and was a close friend of Descartes. He is remembered today largely for his contributions to number theory, especially the theory of Mersenne primes.

Harriet Taylor Mill, nee Harriet Hardy, 1807-1858. Nineteenth-century English thinker. John Stuart Mill's collaborator and wife.

John Stuart Mill, 1806-1873. One of the most noted English thinkers of the 19th century. Known for his liberal rejection of strict utilitarianism, as represented by Bentham.

Carl Mitcham is a philosopher of technology, Liberal Arts and International Studies, and one of the founders of New Directions: Science, Humanities, Policy.

Mocius (Mo Zi, Mo Tzu, Mo Tze, Mo Tse, Mo Di), c. 470 BC – c. 390 BC. Early Chinese philosopher and founder of the Mohist school. Known for his teachings of utilitarianism and universal love.

Michel Eyquem de Montaigne, 1533-1592. Highly influential French humanist philosopher and essayist of the Early Modern period. He revived and reformulated the doctrines of classical skepticism.

Charles-Louis de Secondat, Baron de Montesquieu, 1689-1755. Early modern French thinker, a cornerstone of Enlightenment thought. His greatest legacy today is in political philosophy, through his magnum opus The Spirit of the Laws.

For sites on the subject of G.E. Moore (1873-1958), who believed that the purpose of philosophy is not to debate their truth of common-sense beliefs about the world, but rather to seek an appropriate analysis of their significance.

"I can prove now, for instance, that two human hands exist. How? By holding up my two hands, and saying, as I make a certain gesture with the right hand, 'Here is one hand,' and adding, as I make a certain gesture with the left, 'and here is another.' By doing this, I have proved ipso facto the existence of external things . . . there is no need to multiply examples."

Henry More, 1614-1687. Early Modern English theologian, poet and philosopher. A prominent and prolific member of the Cambridge Platonists, who claimed to demonstrate the existence of god and the compatibility of faith and reason.