Saving money is investment i think ,you are investing in stability of the currency, to trust of your bank and you just believe that tomorrow you will be able same amount of goods as today.
Saving cannot be considered the same as investing, because with investing, you are expecting a return on your investment, or you are making your money grow. With saving, you are basically just accumulating money that will be subject to inflation. Money that is idle cannot be considered investment because it is not generating any kind of profit or return.