Catechism of the Catholic Church §46 — excerpt
When he listens to the message of creation and to the voice of conscience, man can arrive at certainty about the existence of God, the cause and the end of everything.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.