In metaphysics, conceptualism is a theory that explains universality of particulars as conceptualized frameworks situated within the thinking mind. Intermediate between nominalism and realism, the conceptualist view approaches the metaphysical concept of universals from a perspective that denies their presence in particulars outside the mind's perception of them. Conceptualism is anti-realist about abstract objects, just like immanent realism is.
Peter Abelard, a French philosopher, theologian and preeminent logician, put forward the theory of conceptualism.
Metaphysics is the branch of philosophy that examines the basic structure of reality. It is often characterized as first philosophy, implying that it is more fundamental than other forms of philosophical inquiry. Metaphysics is traditionally seen as the study of mind-independent features of the world, but some modern theorists understand it as an inquiry into the conceptual schemes that underlie human thought and experience.
The beginning of Aristotle's Metaphysics, one of the foundational texts of the discipline
Immanuel Kant conceived critical metaphysics as the study of the principles underlying all human thought and experience.
David Hume criticized metaphysicians for trying to arrive at knowledge outside the field of sensory experience.
Boethius's theory of universals influenced many subsequent metaphysicians.