A semiconductor memory device includes an address input circuit for receiving an address signal and outputting an internal address signal corresponding to the received address signal; an address decoder for decoding the internal address signal and outputting a decoded signal; a memory cell array having a plurality of memory cells each capable of storing data, as selected by the decoded signal, the selected memory cell outputting memory cell data; and an output circuit for outputting a truth data and false data at the same time in accordance with the output memory cell data of the selected memory cell.