洛溪BB

While the mouse pleaded, saying," If you would only spare my life, I would be sure to repay your kindness." The lion laughed and let him go.
小老鼠恳求说：“如果你放过我，我一定会报答你的好心的。” 狮子不屑地大笑起来，让它走了。

In nature there are no rewards or punishments, just consequences.
在这个自然界里，没有奖励，没有惩罚，只有结果。（直译，感觉怪怪的）

From the mouse's point of view, we should repay someone who is kind to us.