Georg Philipp Friedrich von Hardenberg

1772 (Oberwiederstedt, Germany) – 1801 (Weissenfels)

Novalis is increasingly seen as one of the most significant and wide-ranging figures in German romanticist culture. Studying law in Jena, he was befriended and encouraged in his thought by Schiller, before meeting and befriending his fellow-student Friedrich Schlegel in Leipzig (they became strong mutual influences), and studying geology under Werner in Freiberg. Tieck, Schelling and the brothers Schlegel all became close friends; Friedrich Schlegel was present at Novalis’s death, and with Tieck, published his work posthumously. Novalis also met Goethe, Herder and Jean Paul (with Fichte, another contemporary influence).

John Locke

1632 (Wrington, England) – 1704 (High Laver)

Locke’s empirically-based account of the mind (like his good friend Newton’s of the physical universe) was a corner-stone of the Enlightenment. His acquaintance and scientific mentor Boyle probably introduced Descartes’ ideas to him; he in turn influenced Rousseau and Voltaire. Wren, Hooke and Dryden were fellow school-students. He was closely involved with the experimentalist group around John Wilkins in Oxford – Willis, Lower and Wren, and Boyle and his assistant Hooke, were members. Huygens confirmed the soundness of Newton’s maths for him; Wycherley was a close friend. Locke told Boyle that miners’ “terrible apprehensions” stopped him getting his barometer underground.

Gottfried Wilhelm Leibniz

1646 (Leipzig, Saxony) – 1716 (Hannover)

Leibniz was perhaps the last great universalist, contributing to disciplines from biology to probability and from theology to linguistics. He was one of the three great 17thC rationalist philosophers, the inventor (independently of Newton) of infinitesimal calculus, and advanced the design of calculating machines. Huygens was a mentor. Leibniz spent several days in deep discussion with Spinoza, met Boyle, Leeuwenhoek and Goldbach, and corresponded extensively with the Bernoullis, von Tschirnhaus, Arnauld, Bayle, Sloane and Oldenburg. Newton and he never met nor corresponded directly. Wallis wrote refusing him permission to teach cryptography to students in Hannover.

Gottfried Wilhelm Leibniz knew…

Gilbert Ryle

1900 (Brighton, England) – 1976 (Whitby)

Ryle, a mainstay of British philosophy, was known for his critique of Cartesian dualism, and coined the phrase ‘the ghost in the machine’. Austin was a colleague at Oxford, Ayer and Dennett (of whom he was very fond) among his students. He supervised Adorno’s thesis; they had a productive relationship despite their very different philosophical heritages. Wittgenstein was a friend — they went on walking holidays together — and said Ryle was one of only two people to understand him (they later fell out, Wittgenstein calling him a charlatan). He told Strawson that he read all of Jane Austen’s novels every year.

Gilbert Ryle knew…

Bertrand Russell

1872 (Trellech, Wales) – 1970 (Penrhyndeudraeth)

One of the key philosophers of the earlier 20th C. If Russell was Whitehead’s protégé (they collaborated for six years), so Wittgenstein, arriving as Russell’s PhD student and rapidly identified by him as a genius, was his. Russell met Moore at Cambridge, had a pivotal meeting with Peano in Paris, pointed out a flaw to the thunderstruck Frege, and named his son after his friend Conrad. He planned some lectures with Lawrence, was a friendly critic to Dewey, and was helped out by Santayana. Shaw, the Webbs, Keynes and Woolf were among his many friends, Quine and Carnap among his many correspondents.

Bertrand Russell knew…

Peter Strawson

1919 (London) – 2006 (London)

Strawson emerged from a group at Oxford University dominated by the twin influences of Ryle (who supported him in his career) and Austin (whom he famously got the better of, and whose influence he diminished); he responded warmly to Ryle (whom he succeeded), but found Austin aloof. Strawson also took on Russell and, their lifelong friendship notwithstanding, Quine; Quine joined in on one of Davidson and Strawson’s panel discussions.

Peter Strawson knew…


François-Marie Arouet

1694 (Paris) – 1778 (Paris)

J.-J. Rousseau was among Voltaire’s multitude of correspondents; though he disapproved of Rousseau’s life, he was civil, and invited him to drink Swiss cows’ milk with him. Voltaire was one of Diderot and d’Alembert’s greatest supporters, writing several articles for their Encyclopédie. The mathematician du Châtelet became his lover and intellectual companion. Boswell, Gibbon, Smith and Casanova all visited him; he misunderstood Congreve’s reticence, and visited Pope at Twickenham. He collaborated with Rameau on several musical pieces, corresponded with Haller and Spallanzani, and antagonised J.-B. Rousseau.

Willard Van Orman Quine

1908 (Akron, Ohio) – 2000 (Boston)

Quine was one of the most significant philosophers of the later 20th C. Whitehead supervised his thesis, gave him his first taste of the incomparability of ‘live’ rather than ‘book’ philosophy, and introduced him to his early hero Russell. Further watershed meetings were with Carnap (Quine became his combative disciple and great friend), and Tarski (another great friend). Quine also met Leśniewski and Łukasiewicz in Warsaw, and Gödel and Schlick in Vienna (Wittgenstein never replied). He corresponded with Piaget, Church, Chomsky and Schrödinger, and described his friend Skinner and himself as Harvard’s Tweedledum and Tweedledee.

Willard Van Orman Quine knew…


Émile-Auguste Chartier

1868 (Mortagne-au-Perche, France) – 1951 (Le Vésinet)

Aron, Canguilhem, Weil and Maurois were all taught by the self-effacing Alain (the pen-name by which Émile-Auguste Chartier is better-known): Canguilhem was strongly influenced by him, while Weil credited him as having had a lasting effect on her philosophy, especially regarding political thought. Alain was one among Rolland’s vast circle of correspondents.

Alain knew…

Isaiah Berlin

1909 (Riga, Latvia) – 1997 (Oxford)

Berlin was praised and criticised for his intellectual breadth — as in his essay, a fox not a hedgehog. Akhmatova flattered herself that their meeting, which affected both deeply, helped start the Cold War (Pasternak and Korney were met on the same trip). Stravinsky (a friend, like Auden, Hobsbawm and Spender) proposed that they collaborate on a cantata. Brodsky said he spoke English like his native Russian, but faster. He took tea with both Freuds; the cowed Shostakovich stayed with him in Oxford. His extensive circle of correspondents ranged from Aron to Wheeler. Spender described him as a baby elephant.

Isaiah Berlin knew…