AN EAGLE stayed his flight and entreated a Lion to make an alliance with him to their mutual advantage. —
一只老鹰停下飞行，并请求狮子与他建立联盟，以互利互惠。 —

The Lion replied, “I have no objection, but you must excuse me for requiring you to find surety for your good faith, for how can I trust anyone as a friend who is able to fly away from his bargain whenever he pleases?’
狮子回答道：“我没有反对，但你必须原谅我要求你找到确保你的诚信的担保人，因为我如何能相信一个能够随意飞离交易的人作为朋友呢？”

Try before you trust.
先试后信任。