Buy: obtain in exchange for payment.Donation: something that is given to a charity, especially a sum of money.人與人之間的善意應該是Buy或是Donation。Buy 期待這份善舉善意同等交換收到些什麼回報。Donation 更多有種自在及不論物質狀態為何精神上有可以與人分享的餘裕富足。