一个很有道理的说法是，如果我们推理和思考的能力足够发达，可以确保我们明白陌生人可以与我们一样受苦或享受生活，那么至少我们中一部分人也会对陌生人有利他行为。
It seems plausible that once our ability to reason and reflect has developed sufficiently enough to enable us to understand that strangers can suffer and enjoy life just as we can, then at least some of us would act altruistically toward strangers, too.