In our modern understanding of reality not even our fellow humans are seen as Thou. The whole point of behaviourism, for example, is to turn human beings into complex objects that can be predicted and controlled without reference to mental events.
If we encounter all of reality as an I-Thou, we will set aside the kind of exploitative and Machiavellian ethic that dominates the world today. Also we will reject a legalistic approach to ethics that is centrally a list of do's and don'ts. Rather, a different kind of ethic is the natural outcome. It's simply that once we experience an other as a Thou, he or she becomes a person with whom we communicate and negotiate -- not a complex object we are free to exploit. Under this ethic, there are things that we simply could not do. For example we could not plunge a harpoon into the living flesh of a whale again and again and again.
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