Thomas Aquinas: Summa Theologiae

Essential Quotes

“This science . . . transcends all others. . . . Now one speculative science is said to be nobler than another, either by reason of its greater certitude, or by reason of the higher worth of its subject-matter. In both these respects this science surpasses other speculative sciences. . . . The purpose of this science . . . is eternal bliss; to which . . . the purposes of every practical science are directed. Hence . . . from every standpoint, it is nobler than other sciences.”

“Since therefore grace does not destroy nature but perfects it, natural reason should minister to faith as the natural bent of the will ministers to charity. . . . Hence sacred doctrine makes use also of the authority of philosophers in those questions in which they were able to know the truth by natural reason . . . but properly uses the authority of the canonical Scriptures as an incontrovertible proof, and the authority of the doctors of the Church . . . merely as probable.”

“Whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity. . . . Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.”