It is not true that Saint Augustine defined lying as necessarily including an intention to deceive.
St. Augustine, in “On Lying”, asks whether the definition of a lie includes the intention to deceive. He leaves the question not definitively answered. But he does counsel that a person should only state what he believes to be true and should not have any intention to deceive. [On Lying, n. 4, last sentence.]
Why doesn’t Augustine simply explain that a lie is still immoral, even when the intention to deceive is absent? It is because the development of doctrine, at that point in time, had not progressed so as to make clear distinctions between each of the three fonts of morality.
Also, even if St. Augustine had answered differently, saying that lying is only lying when one has the intention to deceive, we would be obligated to disagree with him. For the teaching of the Magisterium in Veritatis Splendor is clear and definitive: intrinsically evil acts are immoral regardless of intention or circumstances. This teaching on the immorality of intrinsically evil acts has been taught universally by successive Popes and by the body of Bishops dispersed through the world. This teaching is infallible under the ordinary and universal Magisterium.
Saint Thomas Aquinas improves upon the work of Saint Augustine on lying:
Saint Thomas: “The desire to deceive belongs to the perfection of lying, but not to its species, as neither does any effect belong to the species of its cause.” [Summa Theologica, II-II, 110, 3, Reply to Objection 3.]
This quote requires some explanation, using more modern terminology. The desire to deceive is in the font called intention (first font). The effects are in the font called circumstances (third font). Neither font is capable of changing the moral species (the inherent moral meaning or essential moral nature) of the act, which is determined by the moral object (second font). In other words, intrinsically evil acts, such as lying, are always immoral, regardless of intention or circumstances. Whenever an act is a lie, properly defined, that act is intrinsically evil and always immoral.
It is incorrect to say that St. Augustine defined lying as follows: “A lie consists in speaking a falsehood with the intention of deceiving.” This text is a quote in the Catechism of the Catholic Church, n. 2482; the citation is from St. Augustine, On Lying. However, the quote is mistranslated and taken out of context. First, St. Augustine says: “But it may be a very nice question whether in the absence of all will to deceive, lying is altogether absent.” [On Lying, first sentence n. 4.]
The phrase ‘very nice’ is more accurately translated as ‘very subtle’ [Latin: subtilissime]. Augustine then goes on to discuss the possibilities, but he does not resolve the question as to whether or not a false assertion without the intent to deceive is a lie. He does not state a position on this question. He discusses several different possible definitions of lying, and does not settle on one definition.
However, he leans toward the position that a false assertion is still a lie, even without the will to deceive. For he advises us that we should neither have the will to deceive, nor deliberately assert a falsehood. He says that we should not do either one, whether separately or together.
Saint Augustine: “For there is no need to be afraid of any of those definitions, when the mind has a good conscience, that it utters that which to be true it either knows, or opines, or believes, and that it has no wish to make anything believed but that which it utters.” [On Lying, last sentence n. 4.]
Why then does Augustine define lying as speaking a falsehood with the intention of deceiving? He does not. The whole passage reads as follows.
Saint Augustine: “But whether a lie be at some times useful, is a much greater and more concerning question. Whether, as above, it be a lie, when a person has no will to deceive, or even makes it his business that the person to whom he says a thing shall not be deceived although he did wish the thing itself which he uttered to be false, but this on purpose that he might cause a truth to be believed; whether, again, it be a lie when a person willingly utters even a truth for the purpose of deceiving; this may be doubted. But none doubts that it is a lie when a person willingly utters a falsehood for the purpose of deceiving: wherefore a false utterance put forth with will to deceive is manifestly a lie. But whether this alone be a lie, is another question. Meanwhile, taking this kind of lie, in which all agree, let us inquire, whether it be sometimes useful to utter a falsehood with will to deceive.” [On Lying, first paragraph, n. 5]
St. Augustine doubts whether or not it is a lie to utter what is false without the intention to deceive. But he states that everyone agrees it is a lie if a person willingly utters a falsehood with the purpose (intention) of deceiving. However, this is not put forward by him as the definition of lying, since he adds “whether this alone be a lie, is another question.” In other words, speaking a falsehood with the intention to deceive is certainly a lie, but speaking a falsehood without the intention to deceive might also be a lie; he is not certain.
Therefore, it is false to say that St. Augustine defined lying such that a person ONLY lies when his utterance of a falsehood includes an intention to deceive. Unfortunately, the English text of the CCC gives the impression that Augustine defined lying in just that way. Here is the CCC quote again, ” ‘A lie consists in speaking a falsehood with the intention of deceiving.’ ” [Catechism of the Catholic Church, n. 2482.] It is at best a loose translation of the Latin text of Augustine (accurately quoted in the Latin CCC). But at worst it is a mistranslation affected by a misunderstanding on this point of moral theology by the author or editor responsible for this text.
The Latin text in the CCC, presented as a quote, reads: ” ‘Enuntiationem falsam cum voluntate ad fallendum prolatam manifestum est esse mendacium’ “. And this is an exact quote from the Latin text of On Lying (De Mendacio) as found in: OEuvres complètes de Saint Augustin, Volume 22, p. 7; Augustine, De Mendacio, Caput 4, n. 5. The full Latin text there reads as follows:
“Nemo autem dubitat mentiri eum, qui volens falsum enuntiat causa fallendi : quapropter enuntiationem falsam cum voluntate ad fallendum prolatam, manifestum est esse mendacium.”
My translation is fairly literal: “But none doubts him to be lying who willingly asserts a falsehood for the purpose of deceiving; because of this, it is manifest that the assertion of a falsehood with the intention to lead [someone] into being deceived is a lie.”
The CCC translation has ‘speaking’ instead of ‘asserting’ (or enunciating), which is fine as long as we understand ‘speaking’ broadly, so that any type of indication (such as a nod of the head) would be included. But the phrasing “a lie consists in” is not justified by the Latin text of the CCC, nor by the full text of Augustine. He plainly states that this phrasing is not a definition that would necessarily include every lie. Speaking a falsehood with the intention of deceiving is a lie, but it is not the definition of lying. Augustine considers that it might still be a lie to assert a falsehood without intending to deceive.
See my booklet:
Is Lying Always Wrong?