The Pre-Socratic philosophers are called the first Greek philosophers, who appeared before Socrates and are also referred to as natural philosophers, as well as the earliest of the sophists.

Pre-Socratic philosophy was born in Ionia, in the Greek colonies located on the shores of Asia Minor. The Pre-Socratics combined philosophy with science in their attempt to find the truth and acquire knowledge about the principle or essence of the world.

They were poets, lawmakers, politicians, but mainly scientists, as they dealt with astronomy, geometry, mathematics, theoretical mechanics, and medicine. However, they were also teachers of rhetoric and philosophy who encouraged their students to discuss and question, developing their own ideas and critical thinking. They were distinguished for their wisdom, with the significance that this word acquired in the 6th century BC, with the flourishing of the sciences, when wise men were characterized not only by those who dealt with arts and politics but also with sciences such as mathematics, geometry, astronomy, and medicine.

The Pre-Socratics wrote in poetic and prose language. Their works have been preserved only in fragments, in various ways, throughout the centuries. Our main sources for them and their works are later philosophers such as Plato, Aristotle, Plutarch, Sextus Empiricus, and others.

The series "Pre-Socratics," which includes the ancient text, modern Greek translation, and commentary, consists of 20 volumes. Specifically, it includes:

• Orpheus, Musaeus, Epimenides, Hesiod, Phocus, Cleostratus, Pherecydes, Theagenes, Acusilaus, Seven Sages Complete Works 1
• Thales, Anaximander, Anaximenes Complete Works 2
• Kerkops, Petros, Brontinos, Hippasos, Calliphon and Democedes, Parmeniscus, Epicharmus, Paron, Alcmaeon, Amynias, Iccus Complete Works 3
• Pythagoras 1: Golden Verses Complete Works 4
• Pythagoras 2: Porphyry: Pythagorean Life, Iamblichus: On the Pythagorean Life Complete Works 5
• Pythagoras 3: Pythagorean Fragments Complete Works 6
• Xenophanes Complete Works 7
• Heraclitus of Ephesus Complete Works 8
• Parmenides Complete Works 9
• Zeno, Melissos Complete Works 10
• Empedocles Complete Works 11
• Menestor, Xouthos, Boidas, Thrasylachus, Ion of Chios, Damon, Hippo, Phaleas-Hippodamus, Polykleitos, Oinopides, Hippocrates of Chios - Aeschylus, Theodoros, Philolaus, Eurytus, Archippos, Lysis, Opsimos Complete Works 12
• Archytas, Ocellus, Timaeus, Iketas, Echphantos, Xenophilus, Diocles-Echecrates-Polymnastus-Phanton-Arion, Prorus-Amyclas-Kleinias, Damon and Phintias, Simos, Myonides-Euphranor, Lycon, Catalogue of Iamblichus, Anonymous Pythagoreans, Hearings-Symbols, From the Aristoxenian Pythagorean Decisions and Pythagorean Life Complete Works 13
• Anaxagoras Complete Works 14
• Archelaus, Metrodorus of Lampascus, Cleidemus, Idaios, Diogenes the Apolloniate, Cratylus, Antisthenes the Heraclitean Complete Works 15
• Leucippus, Nessas, Metrodorus of Chios, Diogenes the Smyrnaean, Anaxarchus, Ecaetius the Abderite, Apollodorus, Nausiphanes, Diosim, Bion the Abderite, Bolos Complete Works 16
• Democritus 1 Complete Works 17
• Democritus 2 Complete Works 18
• Sophists 1: Protagoras, Xeniadis, Gorgias, Lycofron, Prodicus, Thrasymachus, Hippias Complete Works 19
• Sophists 2: Antiphon, Critias, Anonymous Iamblichus, Double Speeches Complete Works 20