The lifetime of the 2 + 1 state in 178 Pt was measured by using fast-timing techniques with the high-purity Ge and LaBr 3 : Ce array using the 154 Gd( 28 Si,4n) reaction at a beam energy of 146 MeV. The deduced B(E2,2 + 1 → 0 + 1 ) strength is discussed in relation to the systematics of the previously reported B(E2,2 + 1 → 0 + 1 ) strengths in the light even-even 176-184 Pt isotopes and compared with calculations of the generator coordinate method. The present results support a configuration-mixing interpretation for low-spin states in these light Pt isotopes.