Here are a few excerpts from the Catechism on lying:
2482 “A lie consists in speaking a falsehood with the intention of deceiving.” The Lord denounces lying as the work of the devil: “You are of your father the devil,… there is no truth in him. When he lies, he speaks according to his own nature, for he is a liar and the father of lies.”
2483 Lying is the most direct offense against the truth. To lie is to speak or act against the truth in order to lead someone into error. By injuring man’s relation to truth and to his neighbor, a lie offends against the fundamental relation of man and of his word to the Lord.
2484 The gravity of a lie is measured against the nature of the truth it deforms, the circumstances, the intentions of the one who lies, and the harm suffered by its victims…
2488 The right to the communication of the truth is not unconditional. Everyone must conform his life to the Gospel precept of fraternal love. This requires us in concrete situations to judge whether or not it is appropriate to reveal the truth to someone who asks for it. (1740)
2489 Charity and respect for the truth should dictate the response to every request for information or communication. The good and safety of others, respect for privacy, and the common good are sufficient reasons for being silent about what ought not be known or for making use of a discreet language. The duty to avoid scandal often commands strict discretion. No one is bound to reveal the truth to someone who does not have the right to know it.
Nowhere does the Catechism say that a lie is morally acceptable under certain circumstances. It does not say it is okay to lie in order to secure a greater good (such as protecting someone’s life). It says that one may be silent about the matter so as not to reveal the truth.
Apparently this is a difficult teaching for most of us. We want to promote the good by telling falsehood. However, the Catechism elsewhere teaches: “One may not do evil so that good may result from it.” (1756)
Is it a cultural thing, to attempt to justify lying by the good intentions of the liar? Is there any place on the earth where people speak only the truth? Do you know of any person who speaks only the truth?