Dr. Kreeft's essay at Catholic Vote, "Why Live Action did right and why we all should know that", has provoked a lot of discussion around the internet.
Dr. Kreeft bases his argument on the idea of moral intuition. He says that this moral intuition is what Aquinas speaks of as "synderesis." He says that human moral reasoning begins "with moral experience and imagination and the innate power and habit of moral understanding and judgment, moral 'common sense,' which makes instinctive judgments about moral experiences."
Based on this process, says Doctor Kreeft, when we encounter situations like the problem of Lila Rose and Live Action (which he says is analogous to hiding Jews from Nazis), normal people (i.e., in his words, those who are not "morally stupid") reason thus: "They do not know whether this is an example of lying or not. But they know that if it is, than [sic] lying is not always wrong, and if lying is always wrong, then this is not lying." Dr. Kreeft says that such intuitive reasoning is not infallible, but that when we start reasoning in ways that is contradictory to this intuitive common sense, we are most often going to turn out wrong.
Now, I want to look at some typical renderings of synderesis and see how Dr. Kreeft's aligns with them.
Servais Pinckaers, in "Conscience, Truth, and Prudence," explains that, for Aquinas, synderesis is a habitus, the function of which is "to condemn evil and tend toward the good."
Moral theologian Fr. Wojciech Giertych, O.P. - presently theologian to the Papal household - explains the process of practical moral reason as follows:
[P]ractical reason is endowed with the first principle of action, known as synderesis, which, in an innate and infallible judgment, assesses that good is to be done and that evil is to be avoided.... Practical reason begins with the spark of synderesis, and, using the light it receives from the instinctively known moral law and from its own experience and education, and taking into account the unique circumstances with which it is affronted, it issues a judgment concerning the act to be executed or passes a judgment on the act that took place.
- from "Conscience and the Liberum Arbitrium"
Here we find that "it" - the practical reason - has "instinctive" knowledge of moral law as well, which aligns with Dr. Kreeft's analysis. We also have a distinction, though, that synderesis itself is the very limited idea that good is to be done and evil avoided, and not a matter of judgment about situations, per se. These steps of practical reason are distinct.
While distinct, though, the conscience and the synderesis operations are ontologically related according to modern moral theologians. Cardinal Ratzinger, commenting on the "anthropology of conscience", likens synderesis to the Platonic "memory" of the formal good and true (anamnesis): this is "instilled in our being [but] needs, one might say, assistance from without so that it can become aware of itself." Thus, even though it is an infallible first instinct, synderesis is not to be separated from the elements which "form" the larger conscience. Specifically, Card. Ratzinger mentions the Papacy [and all kinds of Magisterial authority], which are not coming from "without" in regard to synderesis, but function to "bring to fruition... its interior openness to the truth" (see Ratzinger, "Conscience and Truth").
Turning to Veritatis Splendor 59, John Paul II explains that the judgement of conscience "applies to a concrete situation the rational conviction that one must love and do good and avoid evil." Here the entire process of practical reasoning is included. Synderesis is that "rational conviction" about good and evil which then becomes part of the process of analyzing the moral values in given situations.
So, synderesis is, indeed, a moral "intuition" of a sort, which forms the basis of judgments of conscience. It is the essential insight about good and evil which forms the basis for the discernment of conscience. And there are other aspects of "intuitive reasoning" involved in the process of conscience even after synderesis, as Giertych points out, calling these facets the "instinctively known moral law." And, indeed, conscience and synderesis are part of one whole ontological structure of relation to truth in man, as Cardinal Ratzinger points out; thus, there are intuitive aspects to both processes and there are also aspects of both which are open to some kind of formation, which does not deny the "infallible" judgment of synderesis nor the immediate quality of intuition.
How, then, do we evaluate Dr. Kreeft's arguments? Well, I think he is right in noting that intuitions and experience have a value in moral reasoning. The problem with using synderesis in the way Dr. Kreeft has done, though - or even more generally using moral intuition as a closing of debate over issues based on the premise that those whose intuition does not seem to grasp the same things yours does are "morally stupid" - is that the Church does define certain things as "intrinsically evil", and lying is one of them.
John Paul II explains that the purpose of these kinds of definitions is "to serve man's true freedom...; there can be no freedom apart from or in opposition to the truth" (VS, 96). This impact by authority on reason is even on the level of synderesis, as Ratzinger has shown, as the Church's distinctions guide the operation of synderesis toward venues where it applies and where its infallible judgment can be free to work. In this case, the definitive statement that lying is always wrong is directed to freeing synderesis to make this moral sensibility part of our relation to the truth of natural law and a fundamental premise for our moral reasoning. In a sense, it makes our process of practical moral reasoning shorter and easier in cases having to do with lying, where the Church has directed us to use our innate moral sense.
However, the intuition that operates when we encounter a situation of hiding Jews from Nazis, or a situation of Lila Rose spying on Planned Parenthood, is not the infallible intuition of synderesis. Rather, it is an aspect of the intuitive moral process which is involved in the reasoning part of discernment in conscience. Synderesis applies to the situation only in telling us that "lying is bad," from which we can then reason toward conclusions that this, if it is lying, is also bad, which may not seem evident. On the other hand, we might reason that this is not lying, and therefore not necessarily bad - although it might relate to a different intuition of synderesis about what is bad and then be judged to be bad based on that other relation. But the point is that we still require a process of reasoning.
The reason we cannot stop at intuition - as even Dr. Kreeft admits - is evidenced in the title of the work that I took the above theological essays from: Crisis of Conscience: Philosophers and Theologians Analyze Our Growing Inability to Discern Right from Wrong (New York: Crossroads, 1996). This title and the concern of these authors - particularly the direction of Ratzinger's essay which seeks to put even the "infallible" intuition of synderesis in relation to moral authority such as is embodied in the Magisterium - makes plain that intuitions are harder to rely upon in this day and age. We need to form ourselves in virtue and in knowledge of the truth and in conformity to authority in order to use conscience properly and not too-subjectively.