It's not that your life can prove to you that it is what is real, since it is always clouded by reflection, by the inability to bring its own ground to presence, but that the real is in the lives of others. It's that you can affect those lives in ways that cannot be controlled or rescinded - touching the life of an other is what is in earnest, and your own life gains what reality it has only by reciprocal action, which is also called love. This is embodied in the Hegelian fight to the death as much as in the unboundedness of ethical responsibility. They are two of the sides of the same class of event, the proof that reality is revealed in life as it is grasped from the outside, which can only be through others. The tenor of this exceeds anything you can dredge up from within, or so it seems. It puts the world into focus, momentarily but decisively. Notions such as open identity fail to ground ethics if they render otherness an illusion, but most of all because they collapse in the face of the revelation of the other. To step beyond all of this, to realise that as much as it summons you it never actually reaches you, is to step into your true and unmediated solitude.