The invisible navigator

But how do we know that evolution is nonteleological or that any teleology in it must be scientifically unascertainable. Imagine you are on an ancient ship and observe a steersman at the helm. The ship traverses difficult waters and reaches port. You conclude that the vessel’s trajectory at sea was teleological. Why? Two things: you see a steersman controlling the ship’s rudder who, on independent grounds, you know to be a teleological agent; also, you witness the goal-directed behavior of the ship in finding its way home. 

Now imagine a variation on this story. An ancient sailor comes on board a twenty-first century ship that is completely automated so that a computer directly controls the rudder and guides the vessel to port. No humans are on board other than this sailor. Being technologically challenged, he will have no direct evidence of a teleological agent guiding the ship—no steersman of the sort that he is used to will be evident. And yet, by seeing the ship traverse difficult channels and find its way home by exactly the same routes he took with ancient ships guided by human steersmen, he will be in his rights to conclude that a purpose is guiding the ship even if he cannot uncover direct empirical evidence of an embodied teleological agent at the helm. 

http://evoinfo.org/papers/ConsInfo_NoN.pdf