Why does a triplet carbene have a magnetic moment?

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carbene Nonbonding orbitals in triplet and singlet states

A triplet carbene possesses a magnetic moment because it contains two nonbonding electrons that occupy separate orbitals with parallel spins.1

In chemistry, electrons have intrinsic magnetic moments associated with their angular momentum. When two electrons occupy the same orbital, the Pauli exclusion principle requires them to have opposite (antiparallel) spins, which causes their magnetic moments to cancel out, resulting in a singlet state with no net magnetic moment.21

In a triplet state, however, the two nonbonding electrons are distributed between two different available orbitals. Because their spins are parallel, their magnetic moments do not cancel, giving the molecule a net magnetic effect and making it paramagnetic.12