Anibal Jose Baez
Remember, MONEY means LEGAL. And LEGAL is SURETY and ACCOUNTING. It's ALL about the MONEY.
This is not the definition of money of exchange and money of account, rather a simple explanation of their mechanics.
MONEY OF EXCHANGE, is money you have the BENEFIT of using WITHOUT being SURETY for the it. For example, a $20 dollar bill. Your signature is NOT on it, right?
MONEY OF ACCOUNT is money you have the benefit of using, but YOU ARE SURETY for it. Like a CHECK, or a CREDIT CARD, you must SING to use, so YOU become SURETY for that money.