  Closely connected to the boundlessness and unpredictability of action is its irreversibility. Every action sets off processes which cannot be undone or retrieved in the way, say, we are able to undo a faulty product of our hands. If one builds an artifact and is not satisfied with it, it can always be destroyed and recreated again. This is impossible where action is concerned, because action always takes place within an already existing web of human relationships, where every action becomes a reaction, every deed a source of future deeds, and none of these can be stopped or subsequently undone. The consequences of each act are thus not only unpredictable but also irreversible; the processes started by action can neither be controlled nor be reversed.