Quotes from Peter Kreeft

Happiness can get boring, because it is the satisfaction of our desires, and we know what we desire. (Can you desire what you do not know?) Joy never gets boring because it transcends our desires and surprises them with gifts.

Hence man never desires infinite meat, or infinite drink. . . . But non-natural concupiscence is altogether infinite . . . Hence he that desires riches, may desire to be rich not up to a certain limit but to be simply as rich as possible (I-II,30,4).

Cicero famously said, you have no choice between having a philosophy and not having one, only between having a good one and having a bad one. And not to admit that you have a philosophy at all is to have a bad one. For it is one that does not know itself. So how could it know anything else, especially us?

Doesn't certainty about a universal negative require omniscience? Don't you have to have knowledge of everywhere to know that there is no X anywhere?

It's just as dangerous and just as heretical to under—do as to over—do what Scripture says.

The universe is the sum total of all these moving things, however many there are. The whole universe is in the process of change. But we have already seen that change in any being requires an outside force to actualize it. Therefore, there is some force outside (in addition to) the universe, some real being transcendent to the universe. This is one of the things meant by God.

Many people disbelieve in angels because they disbelieve in spirit. They believe only matter exists.

Greed for the things money can buy ("natural wealth") is a bad thing, but it is finite. You can only enjoy a finite amount of food or drink, houses or cars, or even sex. But greed for money ("artificial wealth") is infinite. You can always want more. It's like a drug: you have to have higher and higher doses of it to give you the same "buzz" you used to get from little bits of it. And this never stops. It is Hell's false infinite.

manifests a good person, a good character, a good habit, and also because good deeds gradually form good habits, good character, good persons.

Our only qualification for God's grace is our emptiness, not our fullness; our undeservingness, not our deservingness. 'Those who are well have no need of a physician, but those who are sick. I came not to call the righteous but the sinners.' (Mk 2:17). Similarly, on an infinitely lower level, this book is for empty hearts, not full ones.

Each truth about God known by the mind is a new motive for loving Him with the will.

A habit is a stable disposition to act in a certain way, good or evil. Virtues are good habits; vices are bad habits.