You're correct, however unless you restricted the exchange of currency you'd have people paying no taxes. Imagine two people each get paid $1000 USD and the av

You're correct, however unless you restricted the exchange of currency you'd have people paying no taxes. Imagine two people each get paid $1000 USD and the available currency is doubling weekly. The first person simply holds on to their money in cash. At the end of the week their money is worth half as much. The second person buys Euro's the day their paid, and one week later they can exchange back to USD for $2000. That person effectively paid 'zero' taxes.