For it is necessary in every practical science to proceed in a composite (i.e. deductive) manner. On the contrary in speculative science, it is necessary to proceed in an analytical manner by breaking down the complex into elementary principles.
Thomas AquinasIf... the motion of the earth were circular, it would be violent and contrary to nature, and could not be eternal, since ... nothing violent is eternal .... It follows, therefore, that the earth is not moved with a circular motion.
Thomas AquinasFear is such a powerful emotion for humans that when we allow it to take us over, it drives compassion right out of our hearts.
Thomas AquinasGood and evil are essential differences of the act of the will. For good and evil pertain essentially to the will; just as truth and falsehood pertain to the reason, the act of which is distinguished essentially by the difference of truth and falsehood (according as we say that an opinion is true or false.) Consequently, good and evil volition are acts differing in species.
Thomas Aquinas