1. The fifth way is taken from the governance of the world.
2. We see that things which lack knowledge, such as natural bodies, act for an end, and this is evident from their acting always, or nearly always, in the same way, so as to obtain the best result.
3. Hence it is plain that they achieve their end, not fortuitously, but designedly.
4. Now whatever lacks knowledge cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is directed by the archer.
5. Therefore some intelligent being exists by whom all natural things are directed to their end; and this being we call God.

— From the Summa Theologica, Part 1, Question 1, Article 1, by Thomas Aquinas