What force has the Argument from Design—the attempt to argue to Design, and hence to God, from various alleged signs of it in Nature?

Some preliminary points. First: To establish the reality of God need not be to prove that there exists an actual person meriting that name. Many theologians, for example P. Tillich, have denied that God is any manner of existent. On a fairly simple and attractive interpretation, their view is that ‘God’ names the principle that ethical requirements are creatively powerful. In previous papers I tried to make sense of this principle: there is much that can be said for it. So when talking of ‘design’ I am not presupposing anything as specific as an actual designer.