Søren Aabye Kierkegaard was a Danish theologian, philosopher, poet, social critic, and religious author who is widely considered to be the first existentialist philosopher. He wrote critical texts on organized religion, Christianity, morality, ethics, psychology, and the philosophy of religion, displaying a fondness for metaphor, irony, and parables. Much of his philosophical work deals with the issues of how one lives as a "single individual", giving priority to concrete human reality over abstract thinking and highlighting the importance of personal choice and commitment. He was against literary critics who defined idealist intellectuals and philosophers of his time, and thought that Swedenborg, Hegel, Fichte, Schelling, Schlegel, and Hans Christian Andersen were all "understood" far too quickly by "scholars".
Sosei was a Japanese waka poet and Buddhist priest. He is listed as one of the Thirty-six Poetry Immortals, and one of his poems was included in the famous anthology Hyakunin Isshu. His father Henjō was also a waka poet and monk.
Sosicrates of Rhodes was a Greek historical writer. He was born on the island Rhodes and is noted, chiefly, for his frequent mention by Diogenes Laërtius in his Lives and Opinions of Eminent Philosophers, referencing Sosicrates as the sole authority behind such facts as Aristippus having written nothing. It is inferred that Sosicrates flourished after Hermippus and before Apollodorus of Athens, and, therefore, sometime between 200 and 128 BC. Sosicrates is claimed to have penned a Successions of Philosophers, quoted by both Athenaeus and Diogenes Laërtius. Sosicrates also composed a work on the history of Crete, though neither of the aforementioned works have survived.
Sosigenes the Peripatetic was a philosopher living at the end of the 2nd century AD. He was the tutor of Alexander of Aphrodisias and wrote a work On Revolving Spheres, from which some important extracts have been preserved in Simplicius's commentary on Aristotle's De Caelo.
Sosylus of Lacedaemon was a Greek historian in the 3rd century BC. He would campaign alongside Hannibal throughout the Second Punic War, teaching him Greek and recording the events of his campaign.
Sotion of Alexandria was a Greek doxographer and biographer, and an important source for Diogenes Laërtius. None of his works survive; they are known only indirectly. His principal work, the Διαδοχή or Διαδοχαί, was one of the first history books to have organized philosophers into schools of successive influence: e.g., the so-called Ionian School of Thales, Anaximander and Anaximenes. It is quoted very frequently by Diogenes Laërtius, and Athenaeus. Sotion's Successions likely consisted of 23 books, and at least partly drew on the doxography of Theophrastus. The Successions was influential enough to be abridged by Heraclides Lembus in the mid-2nd century BC, and works by the same title were subsequently written by Sosicrates of Rhodes and Antisthenes of Rhodes.
