Why Crypto-Currencies Are Not Money

It has been argued that the supply of the first significant cryptocurrency, bitcoins, is limited, in the same way that the new supply of gold is limited, relative to above-ground stocks. Therefore, bitcoins have the same supply characteristics as physical gold. This is undoubtedly true, but it does not make bitcoins money. We must disregard the estimated 100,000 world-wide outlets that claim to accept bitcoin in exchange for goods as not material, because the number is too small, and their acceptance of bitcoins is likely to be either strictly limited, or for speculation instead of money