Read the notes, then try the practice. It adapts as you go.When you're ready.
Session Length
~17 min
Adaptive Checks
15 questions
Transfer Probes
8
Metaphysics is the branch of philosophy concerned with the fundamental nature of reality, existence, and being. It asks the deepest questions about what there is, what it means for something to exist, and how the various categories of being relate to one another. From the nature of time and space to the relationship between mind and body, metaphysics investigates the underlying structure of everything that is. The term itself derives from Aristotle's works, where 'ta meta ta physika' referred to the writings that came after his treatises on physics, though the discipline has come to encompass far more than Aristotle could have imagined.
The history of metaphysics stretches from the pre-Socratic philosophers, who sought a single underlying substance (arche) behind all of nature, through the grand systematic metaphysics of Plato, Aristotle, Descartes, Leibniz, and Hegel, to the analytic and continental traditions of the twentieth and twenty-first centuries. While logical positivists in the early twentieth century famously attempted to dismiss metaphysics as meaningless, the discipline experienced a powerful revival through the work of Willard Van Orman Quine, Saul Kripke, David Lewis, and others who demonstrated that rigorous metaphysical inquiry is not only possible but indispensable to science, logic, and everyday reasoning.
Today, metaphysics remains one of the most active areas of philosophy, with vibrant debates about the nature of consciousness, the existence of abstract objects, the reality of possible worlds, the metaphysics of race and gender, and the implications of quantum mechanics for our understanding of fundamental reality. Its questions are not merely academic curiosities; they shape how we understand personal identity, moral responsibility, scientific explanation, and the limits of human knowledge. Whether one is a physicist theorizing about the fabric of spacetime or a cognitive scientist probing the hard problem of consciousness, metaphysical assumptions are always at work beneath the surface.
One step at a time.
The study of what exists and the categories of being. Ontology asks which entities are fundamental, how they relate, and what it means for something to be real. It is the core sub-discipline of metaphysics.
Example: Debating whether numbers exist independently of human minds (Platonism) or are merely useful fictions (nominalism) is an ontological question.
A substance is an independent, enduring entity that bears properties (attributes or qualities). The distinction between what a thing is in itself and the features it happens to have is central to metaphysical analysis.
Example: A bronze statue has the property of being green (from patina) but the bronze substance persists even if the color changes.
The metaphysical relation between cause and effect. Theories of causation attempt to explain what it means for one event to bring about another, with major accounts including regularity theory, counterfactual theory, and powers-based approaches.
Example: Striking a match causes it to light, but philosophers debate whether this is a necessary connection (Hume denied it) or a genuine power inherent in the match.
The debate over whether human agents have genuine freedom of choice. Determinism holds that every event is necessitated by prior causes, raising the question of how moral responsibility is possible if our actions are predetermined.
Example: If the state of the universe at the Big Bang determined every subsequent event, including your reading this sentence, in what sense did you freely choose to read it?
The problem of what makes a person the same person over time and what constitutes the self. Major theories appeal to psychological continuity, bodily continuity, or a persisting soul.
Example: If every cell in your body is replaced over roughly seven years, are you the same person you were a decade ago? The Ship of Theseus puzzle captures this dilemma.
The question of how mental phenomena (thoughts, consciousness, qualia) relate to physical processes in the brain. Dualism posits two distinct substances; physicalism holds that everything is ultimately physical.
Example: When you feel the sharp pain of a pin prick, is that subjective experience identical to a neural firing pattern, or is it something over and above the physical process?
A framework for analyzing modal claims (necessity and possibility). A possible world is a complete, consistent way reality might have been. David Lewis argued that possible worlds are as real as the actual world (modal realism).
Example: The statement 'It is possible that the Earth had two moons' is true if there is at least one possible world in which the Earth has two moons.
Universals are properties or relations that can be instantiated by multiple particular things. The problem of universals asks whether redness, for instance, exists as a single abstract entity shared by all red objects or only as a label we apply.
Example: Two red roses share the property of redness. Realists say redness is a real universal; nominalists say only the individual roses exist and 'redness' is just a name.
More terms are available in the glossary.
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See how the key ideas connect. Nodes color in as you practice.
Walk through a solved problem step-by-step. Try predicting each step before revealing it.
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What you get while practicing:
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