Ancient Philosophy

Ancient philosophy (Pre-Socratic Philosophy) refers to philosophical thought spanning approximately from the 6th century BCE to the 6th century CE, forming the roots of Western intellectual history. This period encompasses systematic modes of thought developed primarily within the frameworks of ancient Greek and Roman civilizations. Ancient philosophers questioned fundamental issues such as the nature of the universe, the source of knowledge, the foundation of ethics, and the purpose of human life through reason, and systematized these inquiries around specific doctrines.

In the ancient world, philosophy was not merely an abstract mode of thinking but also an activity that shaped individual lifestyles. The transition from mythos to logos—that is, from narrative-based traditions to reason-based explanations—is the defining feature of this era. Philosophers questioned not only nature but also social order, moral values, and the methods of acquiring knowledge. From Socrates onward, philosophy came to be seen as a tool for self-knowledge and virtuous living.

Natural Philosophy and Early Thought (Ionian School)

The earliest phase of ancient philosophy is known as natural philosophy. During this period, philosophers sought to identify the fundamental substance (arche) of the universe and understand the order of nature. They departed from mythological explanations by relying on observation and rational reasoning.

Thales and the Milesian School

Thales (6th century BCE), regarded as the historical origin of philosophy, lived in Miletus. He held that the fundamental element of the universe is “water.” Thales’ significance lies in his attempt to explain nature through natural causes rather than divine ones. His students Anaximander and Anaximenes also developed original views on the origin of nature.

• Anaximander identified the fundamental principle of the universe as “Apeiron,” an infinite and indeterminate substance. Apeiron is an endless source from which all things arise and to which they return.
• Anaximenes adopted “air” as the arche. According to him, air generates all other entities through processes of condensation and rarefaction.

These thinkers developed a systematic approach to explaining nature and laid the foundations of scientific thought.

Pythagoras and the Universe of Numbers

Pythagoras (6th century BCE) was a multifaceted philosopher interested not only in mathematics but also in mystical and religious teachings. He held that the essence of the universe is number. The cosmos is ordered according to numerical ratios. He also defended the doctrine of metempsychosis—the transmigration of souls—and asserted that a moral life is necessary for the purification of the soul.

Heraclitus

Heraclitus (of Ephesus) argued that constant change is the essence of the universe. Known for the saying “One cannot step into the same river twice,” he claimed that change is the fundamental nature of reality. For him, the principle that maintains cosmic order is the “Logos”—a rational principle that guides all things. The unity of opposites occupies a central place in his thought: conflict between opposites produces order through struggle.

Parmenides and the Eleatic School

Parmenides opposed Heraclitus’s view of change. He argued that change is an illusion; the only true reality is “the One”—an unchanging, eternal being. His proposition “Being is, non-being is not” initiated a major turning point in the history of thought. Another key philosopher of the Eleatic School was Zeno, who used logical paradoxes to demonstrate the unreliability of knowledge derived from the senses.

Empedocles, Anaxagoras, and Democritus

• Empedocles developed the theory of four fundamental elements—earth, water, air, and fire—to explain the diversity of nature. Two forces, love and strife, unite and separate these elements.
• Anaxagoras argued that everything contains “seeds” (homoiomereia) and that the rational principle “Nous” sets them in motion.
• Democritus proposed that matter is composed of indivisible particles called atoms. Atomism represents a mechanistic and causal view of the universe.

The Sophists and the Pre-Socratic Transformation

In the 5th century BCE, Athens became the center of both political democracy and intellectual life. In this context, the question of whether knowledge and virtue could be taught became one of philosophy’s central debates. Two key figures of this era are the Sophists, who emphasized relativism and rhetoric, and Socrates, who argued that knowledge and virtue could be grounded through reason.

The Sophists

The Sophists are commonly described as “wandering teachers.” These thinkers, who taught in Athens for payment, offered instruction in rhetoric, politics, language, ethics, and law. Their goal was to equip individuals with the knowledge and skills necessary for success in public life, a perspective highly valued in the democratic environment of the time.

Key Characteristics:

• Relativism: The most famous Sophist, Protagoras, claimed “Man is the measure of all things,” arguing that truth varies from person to person. According to him, there are no absolute truths; knowledge and values are relative.
• Rhetoric: For the Sophists, the art of persuasion was paramount. Gorgias maintained that thought is shaped not by reality but by language. He argued that perception of reality is inseparable from linguistic expression. He also articulated radical agnosticism with the statement: “Nothing exists; if anything exists, it cannot be known; if it can be known, it cannot be communicated.”
• Can Virtue Be Taught?: According to the Sophists, virtue (aretê) relates to individual success and social effectiveness. Virtue is not innate but learnable.

The Sophists were criticized by many philosophers, especially Socrates, for promoting moral and epistemological relativism. They were accused of pursuing appearance rather than truth and producing persuasion rather than knowledge.

Socrates

Socrates (469–399 BCE) is a turning point in ancient philosophy. Having left no written works, his ideas are primarily conveyed through the dialogues of his student Plato. He opposed the Sophists’ relativism by defending the existence of universal, justifiable truths.

Key Characteristics:

• Socratic Method (Dialectic): Socrates compelled his interlocutors to think through reciprocal questioning. This method aimed to make individuals aware of their own ignorance. The statement “I know only one thing, that I know nothing” is central to this approach.
• Moral Knowledge: For Socrates, knowledge and virtue are inseparable. If a person knows what is good, they will act accordingly. Thus, wrongdoing stems from ignorance.
• Irony and Maieutics: Through irony, he questioned his interlocutor’s assumed knowledge; through maieutics (the art of midwifery), he helped them give birth to their own truths.
• Death and Virtue: Socrates was tried and sentenced to death in Athens on charges of impiety and corrupting the youth. Yet he feared death less than he feared abandoning truth, making philosophy a way of life.

Socrates emphasized individual conscience and rational principles, laying the foundations of ethical philosophy. He profoundly influenced later philosophers such as Plato and Aristotle. Through him, philosophy shifted from nature-centered explanations to human-centered ethical and epistemological inquiries.

Plato and Aristotle

The classical period of ancient Greek philosophy reached its peak with the systematic thought of Plato and Aristotle. These philosophers left enduring impacts not only on knowledge and being but also on ethics, politics, art, and natural philosophy.

Plato (Eflatun) – The World of Forms

Plato (427–347 BCE), a student of Socrates and teacher of Aristotle, founded the first institution of higher learning, the Academy. Plato’s philosophy is built on two fundamental levels of reality: the changing world of the senses and the unchanging world of Forms.

Key Views:

• Theory of Forms: For Plato, true knowledge (episteme) is not derived from sensory objects but from the immutable and perfect realm of Forms. For example, the true reality of justice, beauty, or goodness exists in this realm; objects in our world are merely faint reflections of these Forms.
• Allegory of the Cave: This is Plato’s most famous metaphor for explaining his theory of knowledge. People in the cave mistake shadows for reality, while the philosopher escapes the cave and perceives the light of the Forms.
• Theory of the Soul: The human soul consists of three parts: reason (logistikon), spirit (thymoeides), and appetite (epithymetikon). A virtuous person is one whose reason governs the soul and harmonizes its three parts.
• State and Politics: In his work Republic (Politeia), Plato argues that the ideal state is governed by philosopher-kings. He correlates the three classes of society—rulers, guardians, and producers—with the three parts of the soul.
• Critique of Art: For Plato, art imitates the physical world, which itself is an imitation of the Forms. Thus, art is “an imitation of an imitation” and can distance people from truth.

Plato established systematic foundations in metaphysics, epistemology, ethics, and political philosophy and profoundly influenced Christian philosophy.

Aristotle – Systematic Analysis of Reality

Aristotle (384–322 BCE), a student of Plato, departed from his teacher’s idealism and developed a more empirical philosophy. He founded the Lyceum. He systematized philosophy across numerous fields, from logic and natural science to ethics and politics.

Key Views:

• Metaphysics and the Four Causes: Aristotle argued that to understand any entity, one must identify four causes: material, formal, efficient, and final. The final cause (telos) explains purposeful tendencies in nature.
• Form-Matter Distinction: All entities are a unity of form and matter. For example, a statue consists of bronze (matter) and its shape (form). This view offers an alternative to Plato’s Theory of Forms.
• Logic: Aristotle is the founder of formal logic. He analyzed the structure of thought through categories, propositions, and syllogisms.
• Ethics: In his Nicomachean Ethics, Aristotle’s virtue ethics is based on the “golden mean.” Virtue lies between two extremes. For example, courage is the mean between cowardice and recklessness.
• Politics: He defined humans as “zoon politikon”—political animals. The good life is possible only within society. The best form of government is a mixed regime dominated by the middle class.
• Art and Aesthetics: Although he viewed art as imitation, Aristotle welcomed it positively. In his Poetics, he analyzed tragedy and the concept of catharsis (purification).

Aristotle’s thought influenced Islamic philosophy, medieval Christian thought, and the Enlightenment. He is the pioneer of the scientific method, classification, and systematic reasoning.

Hellenistic Philosophy

Hellenistic philosophy extends from the late 4th century BCE to the Roman period. With the dissolution of political structures and the individual’s withdrawal from public life, philosophy became focused on personal happiness, tranquility (ataraxia), and freedom. Three major schools emerged in this context: Epicureanism, Stoicism, and Skepticism.

Epicureanism

Founded by Epicurus (341–270 BCE), this school aims at achieving inner peace through hedonism. Epicurus combined philosophy in his school, called “The Garden,” with principles of friendship, simple living, and harmony with nature.

Key Views:

• Hedonistic Ethics: For Epicurus, the goal of a good life is pleasure, but this pleasure is not sensual excess; rather, it is the absence of pain and mental tranquility (ataraxia).
• Living in Accordance with Nature: Unnecessary desires must be suppressed; one should be content with natural and necessary things (e.g., food, shelter, friendship).
• Fear of Death and the Gods: Epicurus argued that death is not to be feared, because when we are alive, death is not present, and when we die, we no longer exist. Even if gods exist, they do not interfere in the universe.
• Atomism: Epicurus adopted Democritus’s atomism, explaining nature through chance and necessity. The universe operates through material processes, not divine order.

Stoicism

Founded by Zeno in the 3rd century BCE, Stoicism seeks inner freedom by cultivating wisdom in the face of fate and natural order. Key representatives include Cleanthes, Zeno of Citium, Chrysippus, and in the Roman period, Seneca, Epictetus, and Marcus Aurelius.

Key Views:

• Logos and Nature: The universe is governed by a rational principle (logos). Living in accordance with nature means living rationally.
• Determinism: Everything occurs according to natural laws. Humans cannot change these necessities but can respond to them with wisdom and calmness.
• Virtue Ethics: True virtue is independent of external conditions. Wealth, fame, health, and other external goods are considered “indifferent” (adiaphora).
• Freedom: The Stoic sage is sovereign only over his inner world, not the external world. Thus, he can be happy.

Skepticism

Another major trend in Hellenistic philosophy is skepticism, which claims that certain knowledge is unattainable. Its first founder was Pyrrho (360–270 BCE), and its systematic formulator was Sextus Empiricus.

Key Views:

• Epoché (Suspension of Judgment): Skeptics argue that we cannot achieve certainty on any issue; therefore, judgment must be suspended.
• Ataraxia (Mental Tranquility): Avoiding knowledge claims and maintaining equal distance from all views leads to mental peace.
• Distinction Between Appearances and Belief: Skeptics live according to appearances alone, acting on probabilities rather than absolute knowledge.

Characteristics of Hellenistic Philosophy

• Individual, not public philosophy: Philosophy shifted from guiding public life to focusing on the individual’s inner life.
• Pursuit of happiness: The central aim of all schools was to achieve inner peace and freedom for the individual.
• Eclecticism and universalism: Under Roman influence, Hellenistic philosophies began to blend; a universal model of the human being replaced local traditions.

Roman Period and Late Ancient Philosophy

During the Roman Empire, Greek philosophy was synthesized with Latin culture and became a subject of interest for Roman aristocrats, intellectual circles, and Christian thinkers. During this period, Stoicism, Platonism, and Aristotelianism were reinterpreted, and the first Christian philosophers emerged.

Roman Stoicism

In Rome, Stoicism was embraced primarily as an ethical doctrine, advocating inner resilience and moral consistency amid political turmoil. It is especially associated with three major thinkers:

Seneca (4 BCE–65 CE):

• Advisor to Emperor Nero, Seneca treated Stoic thought with a moral focus.
• He defended the nobility of virtue and living in accordance with nature.
• His writings address wisdom, the value of time, fear of death, and coping with passions.

Epictetus (50–135 CE):

• A former slave, Epictetus argued that humans can freely choose their attitude toward events beyond their control.
• In his Enchiridion (Handbook), he transformed Stoicism into a practical guide for daily life.

Marcus Aurelius (121–180 CE):

• Emperor and philosopher, Marcus Aurelius presented Stoic ethics in his Meditations as personal reflections.
• Themes such as harmony with cosmic order, duty, and self-mastery are central.

Neoplatonism (Neoplatonism)

One of the most influential schools of late ancient philosophy is Neoplatonism. This movement transformed Plato’s philosophy into a metaphysical system centered on spiritual ascent and union with the Divine. Its founder was Plotinus (205–270 CE), and his ideas were systematized by his student Porphyry.

Key Views:

• The One: There exists a transcendent principle beyond all beings, the source of everything: “The One.” This principle is understood as divine but is indefinable and absolutely unified.
• Emanation: Beings emerge from The One through a process of overflow: The One → Intellect (Nous) → Soul (Psyche) → Matter.
• Ascent of the Soul: The human soul is exiled in the material world and must strive to return to The One through knowledge, virtue, and mystical experience.
• Interpretation of Plato: Plotinus reinterpreted Plato’s Theory of Forms as part of a metaphysical hierarchy, transforming it into a spiritual philosophy.

Aristotelianism and Eclecticism

In the Roman period, Aristotle’s works attracted interest primarily in logic, natural science, and ethics, especially as formal logic was taught in schools. Alongside this, an eclectic philosophy that blended various doctrines became widespread. Thinkers like Cicero exemplified this trend.

Cicero (106–43 BCE):

• He synthesized Stoic, Epicurean, and Academic views, adapting them for public life and legal philosophy.
• He sought to ground Roman public morality in philosophy.

Christianity and Philosophy

As Christianity rose in the late Roman Empire, philosophy clashed with new religious views but gradually became a tool for constructing its conceptual framework. Some philosophers sought to synthesize Christianity with ancient philosophy.

• Justin Martyr (100–165 CE): He attempted to ground Christianity within the Platonic tradition.
• Clement and Origen: They sought reconciliation between Platonism and Christianity.
• Augustine (354–430 CE): Augustine, the most important figure of late antiquity and early Christian thought, integrated the Platonic heritage with Christianity. His ideas on God, the soul, time, and knowledge shaped medieval philosophy.

Characteristics of Late Ancient Philosophy:

• Religious and metaphysical orientations strengthened.
• Individual salvation and spiritual ascent came to the fore.
• Philosophy merged with religious thought, acquiring a theological framework.

Glossary of Key Terms

• Arche: The first cause or fundamental substance of all things (Thales: water; Anaximenes: air).
• Logos: Reason, order, or universal law (especially central in Stoicism).
• Episteme: Certain, scientific knowledge (Plato and Aristotle).
• Ataraxia: Mental tranquility and peace (Epicurus and Pyrrho).
• Emanation (Sudûr): The process by which beings emerge from The One (Neoplatonism).
• Eudaimonia: Human flourishing through a happy and virtuous life (Plato, Aristotle).
• Form/Idea: The immutable essences that Plato believed exist beyond the sensory world.
• Teleology: The belief that everything has a purpose (especially in Aristotle).
• Epoché: The suspension of judgment (Skepticism).
• Apatheia: Freedom from the influence of passions (Stoic virtue).

Geographical Schools and Representatives:

• Ionia (Western Anatolia – Miletus): Thales, Anaximander, Anaximenes
• Ephesus: Heraclitus
• Elea (Italy): Parmenides, Zeno
• Samos – Southern Italy: Pythagoras
• Athens: Socrates, Plato, Aristotle
• Corinth – Rome: Epictetus
• Alexandria (Egypt): Plotinus, Origen
• Cyprus: Zeno (Stoicism)
• Syracuse (Sicily): Gorgias