You know, what happens in Astro Disaster isn’t really what the Catechism was talking about, but it does bring to mind that part of paragraph 1789 which, referencing scripture, reminds us that “it is right not to… do anything that makes your brother stumble." (Ba-dom-dom)
No, what the Catechism is talking about is what the New Catholic Encyclopedia of 1967 defines as Scandal. “In moral theology… scandal signifies not so much something shameful and therefore likely to cause a reaction of indignation and outrage, but something that provides occasion and incitement to the sin of another. It is not necessary that sin be actually committed in consequence of it; it is enough that the evil act or word provides incitement to wrongdoing, and it is precisely in this that the sin of scandal consists.”
The tricky part, as St. Paul pointed out, is that scandal can exist "even when the particular actions involved are in themselves good or at least indifferent. If we perceive that scandal is the likely result of a certain act, we should refrain from that act, if this can easily be done, while making it clear at the same time that we are not refraining from it because we regard it as wrong. St. Paul, after making it clear to the Corinthians that they were permitted to eat food even though it had been sacrificed to idols, nevertheless went on to advise them: "Still, take care lest perhaps this right of yours become a stumbling block to the weak... if food scandalizes my brother, I will eat flesh no more forever, lest I scandalize my brother" (1 Cor 8.9, 13)."
Tough stuff. Believe me, I know. But nobody said it would be easy. Well, except for that Oprah And Friends: A Course in Miracles thing. I meant nobody you should take seriously.