The transition from the paternalistic paradigm of the Hippocratic tradition to the present model of shared decision making has altered the patient–doctor relationship. This change has engendered conflicts between patients and physicians, especially in pediatric medicine, where the patients are depen­dent on their parents because of their inability to consent to an intervention independently. Navigating this complex relationship can become particularly fraught when medical futility is invoked. This situation is complicated further by the divergent approaches to shared decision making among physicians and the ethical perspectives these positions reflect. Catholic doctrine on the role of parents in medical-ethical decision making provides insight into navigat­ing these difficult clinical issues and ideologies.

Germain Grisez’s philosophical argument for respecting human life has been developed by fellow new natural law (NNL) theorists and applied to a range of lethal actions, for its conclusion is vast: intending the death of any human being as a means or an end is wrong in itself. For some Thomists, the NNL view on killing is both lax and rigorist: They consider it lax because its narrow criterion for what is “intended” leaves out some acts, especially ones related to abortion, that the critics consider murder. And they consider the NNL view rigorist insofar as it apparently rules out the death penalty, contrary to the Thomistic tradition and perhaps even heretically. However, the most salient philosophical arguments for exceptions to the principle against intending anyone’s death are weaker than the case for any given premise of the contrary NNL argument. Nevertheless, some NNL theorists’ arguments on life are unsound, some can be defended better than they have been, and some nonphilosophical objections based on theological authority require more exploration.

The New Natural Law (NNL) theory offers a distinctive account of the nature of intention and human action and, accordingly, of what aspects and consequences of a human agent’s performance should be considered outside the intention (praeter intentionem). In part, the distinctive features of the account follow from a methodological decision to consider human action from the perspective of the agent of that action, the first-person agential standpoint. This theory of action and intention has nevertheless been subject to considerable criticism. The view is held by many to be too first-personal and to provide inadequate “constraints” on what an agent intends when his performance will inevitably and foreseeably be accompanied or followed by states of affairs in which individuals are harmed.

Fifty years of debate have strengthened Germain Grisez’s 1965 interpretation of St. Thomas Aquinas’s famous article on the natural law in Summa theologiae I-II.94.2. Revisiting Grisez’s argument in light of these developments reveals that his “gerundive interpretation” of the first principle of practical reason is not only Thomistic, but essentially Aquinas’s interpretation.

The major difference between “new” and “old” natural law approaches to sexual ethics is that for new natural law theorists the moral evaluation of sex acts is always determined with reference to that basic form of human flourishing which is called marriage; old natural law theorists determine the morality of sex acts also (or primarily) with reference to the natural purpose of the sexual faculties. Ultimately, the old approach relies implicitly on prior value judgments to distinguish biological facts that are axiologically or morally relevant from those that are not. It also appeals to values to ground the wrongness of immoral sex acts. In its pure form, the old natural law approach to sexual ethics lends itself to a misunderstanding of the unitive aspect of marriage. More broadly, an accurate understanding of new natural law does not run afoul of the correct interpretation of “nature” in natural law.

Some critics question new natural law theorists’ conception of the common good of the political community, namely, their interpretation of St. Thomas Aquinas and the conclusion that the political common good is primarily instrumental rather than intrinsic and transcendent. Contrary to these objections, the common good of the political community is primarily instrumental. It aims chiefly at securing the conditions for human flourishing. Its unique ability to use the law to bring about justice and peace and promote virtue in individuals may make the common good of the political community critically important. Nevertheless, it is still not an intrinsic aspect of human flourishing. Unlike the family or a religious group, membership in a political community is not an end in itself.

New natural law theory (NNLT) holds that the basic moral principles are prescriptions to pursue the goods to which our nature orients us. Since God is the author of our nature and intelligence, these moral principles are part of his plan for creation. These principles can be known prior to knowing that God exists and prior to knowing that they are in fact directives from him. Nevertheless, since God’s plan includes our active cooperation, morally good acts cooperate with God’s providence, and morally bad acts substitute one’s subjective preference for God’s truth. Thus natural law principles direct us to a unified ultimate end, namely, the fulfillment of God’s plan. Therefore God and our relationship with him have a central place in NNLT.

According to David Benatar’s asymmetry argument, the transition from nonexistence to existence is always a harm, and procreation always a pro tanto wrong. This argument fails to reach its anti-natalist conclusion if we maintain the view that there is no temporal relationship between our worldly lives and our afterlives. On this view, since anyone who will be freely procreated has an existence in the afterlife that is atemporal with respect to worldly time, procreators do not move those they procreate from nonexistence to existence and so do not harm them. This view provides a reason to reject Benatar’s stringent “life worth starting” criterion for procreation.

In the sphere of end-of-life care, the fear of being a burden on loved ones is a significant factor in patients seeking assisted suicide or euthanasia. The claims of altruism and love that support such decisions are misplaced, and the possibility of being a burden must be reimaged within a proper anthropology. Allowing oneself to be a burden is a significant aspect not only of loving human relationships, but of a human nature that is essentially dependent and created in the image of God.

The Fathers of the Second Vatican Council recognized that the doctrine of the Incarnation is specifically concerned with the coming of Christ to free mankind from bondage to both original and personal sin. Original justice and original sin also can be examined through the dogma of the Immaculate Conception. By considering these concepts through the original moment of Mary’s conception, we gain a better understanding of the moment that each person is conceived. Thus a proper understanding of the Immaculate Conception will help us develop a better definition of human conception.

In their article “Debate Ethics of Embryo Models from Stem Cells,” Nicolas Rivron and colleagues call for a debate on stem cell–derived human embryo models. They first ask four questions regarding ethics and embryo models, and then give four recommendations to investigators and regulators. Understanding the nature of embryo models is crucial to determining their treatment. If they are human organisms, they should be protected by existing guidelines for ethical research. For instance, the good—which for humans includes organismal flourishing—precludes experimentation on embryonic humans. However, investigators do not know with certainty whether embryo models are equivalent to embryos. Therefore, investigators must halt experiments, evaluate data, and engage in debate before continuing with research.

An unquestionably important biological question is whether human beings are the product of chance or of purpose in the evolutionary process. Charles Darwin did not accept purpose in biological evolution, a view not shared by his colleague Alfred Russel Wallace. The controversy has remained ever since, and while many experts argue against purpose in biological evolution, many others defend it. This paper reflects on this biological and ethical problem, relating it to the possible existence of a plan that governs and shapes the evolution of living beings and that is ultimately responsible for the development of Homo sapiens.