Metaphysics is the branch of philosophy that investigates the most fundamental structure of reality.
Metaphysics is the branch of philosophy concerned with the most basic features of reality. Traditionally, it has been understood as the study of mind-independent aspects of the world. However, some philosophers interpret it instead as an investigation into the conceptual framework through which human beings understand reality. Thinkers such as Aristotle described metaphysics as first philosophy, suggesting that it is more foundational than any other philosophical discipline.
Metaphysics addresses a wide range of highly general and abstract questions. It examines the nature of existence, the characteristics shared by all entities, and the ways in which beings can be categorized. One major distinction is between particulars and universals. Particulars are individual, unique entities—such as a specific apple—while universals are general features that multiple particulars can share, such as the color red. Modal metaphysics explores what it means for something to be possible or necessary. Other central concerns include the nature of space, time, and change; the relationship between causation and the laws of nature; the connection between mind and matter; and debates over determinism and free will.
Metaphysical inquiry typically relies on rational intuition and abstract reasoning, though some approaches incorporate empirical insights from science. Because of its abstract scope, metaphysics has often been criticized for the reliability of its methods and the meaningfulness of its claims. Nevertheless, it remains deeply relevant, since many academic disciplines depend—often implicitly—on metaphysical assumptions.
The origins of metaphysical thought can be traced to antiquity. Early reflections on the nature and origin of the universe appear in the Upanishads of ancient India, in Taoist philosophy in China, and in pre-Socratic Greek philosophy. In the medieval West, debates about universals were shaped by the philosophies of Plato and Aristotle. During the modern period, systematic metaphysical theories emerged, many influenced by idealism. In the twentieth century, traditional metaphysics—and especially idealism—faced strong criticism, leading to new approaches and methods.
Definition
Metaphysics studies the most fundamental features of reality, including existence, objects and their properties, possibility and necessity, space and time, change, causation, and the relation between mind and matter. It is one of the oldest branches of philosophy.
Its exact nature, however, is debated. Some philosophers define metaphysics broadly as the study of fundamental questions about reality or the essences of things. Others prefer a more detailed account that characterizes it by listing its principal areas of inquiry. Certain definitions are descriptive, explaining what metaphysicians in fact do, while others are normative, prescribing what metaphysics ought to address.
Historically influential accounts in ancient and medieval philosophy describe metaphysics as the science of first causes or as the study of being qua being—that is, what all beings share and how they fall into basic categories. In modern philosophy, its scope expanded to include issues such as the mind–body distinction and free will. Following Aristotle, some thinkers continue to regard metaphysics as “first philosophy,” the foundational discipline upon which others depend.
A significant shift occurred with Immanuel Kant, who reinterpreted metaphysics through the lens of critical philosophy. Rather than attempting to describe reality beyond experience, Kant focused on the principles that structure human thought and experience. He distinguished between transcendent metaphysics, which aims to describe reality beyond sensory experience, and a critical approach that analyzes the conceptual conditions of knowledge. Later, P. F. Strawson developed this perspective further by distinguishing between descriptive metaphysics, which clarifies our existing conceptual scheme, and revisionary metaphysics, which seeks to improve it.
Metaphysics differs from the individual sciences in its level of generality. While physics studies physical entities, biology investigates living organisms, and anthropology examines cultures, metaphysics asks about the most general structures underlying all such domains. Whether this distinction is sharp or gradual remains a matter of debate.
Etymology
The term metaphysics derives from the Greek words metá (“after,” “beyond”) and phusiká (“physics” or “natural things”). It comes from the phrase ta metá ta phusiká, meaning “the things after the Physics.” The title was likely assigned by Andronicus of Rhodes, an editor of Aristotle’s works, to indicate that the text should be read after the Physics. The term entered English in the sixteenth century via the Latin metaphysica.
Branches of Metaphysics
Metaphysics is often divided into general and special branches.
General metaphysics, or ontology, examines the most fundamental aspects of being. It studies what entities share and how they can be classified into basic categories such as substance, property, relation, and fact. Ontologists investigate how these categories relate to one another and form a comprehensive framework for understanding everything that exists.
Special metaphysics approaches being from narrower perspectives.
-
Metaphysical cosmology explores changeable entities and the structure of the world as a whole across space and time.
-
Rational psychology examines the metaphysical foundations of the mind, including its relation to matter and the freedom of the will.
-
Natural theology investigates the concept of the divine and its role as a first cause.
In the late twentieth century, applied metaphysics emerged, exploring how metaphysical theories inform other areas such as ethics, philosophy of religion, artificial intelligence, economics, sociology, medicine, and psychiatry.
A further development is meta-metaphysics, the study of the nature and methods of metaphysics itself. It asks how metaphysics differs from science and other philosophical disciplines and whether its claims are meaningful or justified.
Central Topics
Existence and Categories
Existence is often regarded as one of the most fundamental metaphysical concepts. To exist is to belong to reality rather than to imagination. Philosophers debate whether existence is a property of individuals or of properties, whether all entities exist in the same way, and whether there are degrees or modes of existence. For example, Plato argued that ideal Forms possess a higher degree of reality than material objects.
Theories of categories aim to provide a systematic inventory of all types of being. Aristotle proposed ten categories, treating substance as primary. Immanuel Kant later offered twelve categories organized under quantity, quality, relation, and modality. Contemporary philosophers continue to refine categorical systems.
A common distinction is between concrete objects, which exist in space and time and participate in causal relations, and abstract objects, such as numbers or sets, which do not.
Particulars and Universals
Particulars are individual entities—such as a specific person or object—while universals are repeatable features that multiple particulars can share. Many philosophers hold that particulars instantiate universals.
One influential account, associated with John Locke, describes particulars as substrata that bear properties. In contrast, inspired by David Hume, bundle theorists argue that particulars are nothing more than collections of properties. Some propose the idea of haecceity—a unique “thisness”—to explain individuality.
The relationship between parts and wholes is studied in mereology. Philosophers debate whether composite objects truly exist or whether reality ultimately consists only of fundamental particles arranged in certain ways.
Metaphysics remains a central and enduring field of philosophy. Whether understood as the study of being itself, the analysis of conceptual frameworks, or the foundational inquiry underlying all other disciplines, it continues to shape how we think about reality at its deepest level.
.jpg)
.jpg)