The philosophers before Socrates, before 400 BCE, are known as the presocratic philosophers. In 30 Philosophers, the western giant Heraclitus is used in chapter 7 to represent the presocratics. Others are used in the overall telling of the epic story of modern human thought, and they include Thales, Pythagoras, Anaximander, Parmenides, and Democritus. These thinkers laid the foundation for Western philosophy by shifting the focus from mythological explanations of the world to rational inquiry and natural observation.
Heraclitus, often called the “Weeping Philosopher,” took center stage in these early explorations by emphasizing the role of change and flux in the universe. He famously declared, “You cannot step into the same river twice,” highlighting his belief that the only constant is change. Heraclitus viewed the world as a dynamic interplay of opposites, unified by a principle he called the logos, a rational order underlying all things. His ideas challenged thinkers to grapple with the paradox of stability and transformation.
Other presocratic thinkers offered groundbreaking perspectives. Thales, often credited as the first philosopher, proposed that water was the fundamental substance of all things, and he is often credited with the earliest known attempts at scientific experimentation. Anaximander suggested the apeiron, an indefinite or boundless principle, as the source of existence, while Pythagoras combined mathematical precision with mysticism, claiming numbers held the key to understanding reality. Parmenides introduced the concept of being as eternal and unchanging, starkly opposing Heraclitus’s vision of constant flux. Finally, Democritus, known for his atomic theory, envisioned the universe as composed of indivisible particles moving through the void. Together, these thinkers set the stage for Socrates and the classical age of philosophy.