You're agreeing with him. Gold and tulips are commodity currencies, they have value outside of their uses as a currency. The dollar and bitcoin are not commod

You're agreeing with him. Gold and tulips are commodity currencies, they have value outside of their uses as a currency. The dollar and bitcoin are not commodity currencies, i.e., they have no value or use outside of their use as currencies. Whether bitcoin can be called a 'fiat' currency is debatable because it's not a currency "by fiat", though "fiat" currency has come to mean a non-commodity currency.