For Hegel, the true universal is not an abstract common feature that we extract from particulars (as in traditional logic). It is concrete: it contains within itself the moment of particularity and individuality. The concept is the unity of universal, particular, and individual.

The abstract universal (e.g. "red" as a property shared by many things) leaves the particulars outside it. The concrete universal is the whole that differentiates itself into its moments and remains one in that differentiation. The state, the work of art, the living organism—each is such a whole. Philosophy, for Hegel, has to grasp these concretes in their concept, not reduce them to abstract commonalities.

This is why Hegel is critical of the "understanding" that holds concepts fixed and separate. Reason is the capacity to think the concrete universal—the identity of identity and non-identity.