Augustine is actually describing something paradoxical: love that operates outside economics. Most people assume affection works like a bank account—you invest a certain amount and expect reasonable returns—but he's suggesting that authentic love abandons all ledgers entirely. When you truly love someone, you don't mentally track whether they've earned your kindness or whether you're getting a fair exchange; you simply pour out what you have. A parent who sits with a rebellious teenager at 2 a.m., not to earn gratitude but simply because presence matters, understands this without needing the philosophy.