Metaphysics is the branch of philosophy that studies the basic nature of reality. It asks what exists, what it means for something to exist, and how things can remain the same while changing over time. Students need this cheat sheet because metaphysical ideas appear in debates about science, religion, personal identity, free will, and the mind.
A clear reference helps students compare abstract views without losing track of the main questions.
The core concepts include being, substance, properties, identity, causation, time, possibility, and necessity. Metaphysical arguments often begin with a key claim, such as “everything that exists is physical” or “persons are more than bodies.” Students should focus on how each view defines reality and what evidence or reasoning supports it.
Strong metaphysical thinking means asking what must be true for an idea, object, or person to exist as it does.
Key Facts
- Metaphysics asks the core question: What is ultimately real?
- Ontology is the study of what exists, including objects, minds, numbers, properties, events, and possible worlds.
- A substance is often defined as something that exists independently, while a property is a feature that belongs to or describes something.
- The principle of identity states that each thing is itself, often written as A = A.
- The law of noncontradiction states that a claim cannot be both true and false in the same sense at the same time.
- Personal identity asks what makes a person the same person over time, such as memory, body continuity, soul, or psychological continuity.
- Causation is the relation in which one event or condition helps produce another event or condition.
- Modality studies possibility and necessity, where a necessary truth must be true and a possible truth could be true.
Vocabulary
- Metaphysics
- Metaphysics is the branch of philosophy that studies the most basic features of reality and existence.
- Ontology
- Ontology is the study of what kinds of things exist and how they can be grouped.
- Substance
- A substance is something considered to exist in its own right rather than merely as a feature of something else.
- Property
- A property is a quality, feature, or characteristic that something has, such as color, shape, or mass.
- Dualism
- Dualism is the view that reality includes two fundamentally different kinds of things, often mind and matter.
- Materialism
- Materialism is the view that everything that exists is ultimately physical or depends on the physical.
Common Mistakes to Avoid
- Confusing metaphysics with physics is wrong because metaphysics asks broader questions about what reality is, while physics studies measurable natural processes.
- Treating every opinion as equally supported is wrong because metaphysical claims still need reasons, clear definitions, and logical consistency.
- Mixing up substance and property is wrong because a substance is the thing being described, while a property is a feature of that thing.
- Assuming change destroys identity is wrong because many theories explain how something can change some properties while remaining the same object or person.
- Using the word real without defining it is a mistake because different views may mean physical, mental, abstract, independent, or experienced reality.
Practice Questions
- 1 A chair is painted from red to blue. Explain one way it can change properties while still being the same chair.
- 2 Classify each item as substance, property, or event: a basketball, roundness, a glass breaking, a tree, and being green.
- 3 If materialism says everything real is physical, what challenge might dreams, thoughts, or numbers create for that view?
- 4 Two people have identical memories, personalities, and beliefs, but only one has the original body. Which one is the same person, and what does your answer assume about personal identity?