Let V be the m × m upper-left corner of an n × n Haar-invariant unitary matrix. Let λ 1 , · · · , λ m be the eigenvalues of V. We prove that the empirical distribution of a normalization of λ 1 , · · · , λ m goes to the circular law, that is, the uniform distribution on {z ∈ C; |z| ≤ 1} as m → ∞ with m/n → 0. We also prove that the empirical distribution of λ 1 , · · · , λ m goes to the arc law, that is, the uniform distribution on {z ∈ C; |z| = 1} as m/n → 1. These explain two observations byŻyczkowski and Sommers (2000).