The compelling idea at the core of classical act-utilitarianism, Portmore tells us, is that ‘an act's deontic status is determined by the agent's reasons for preferring its outcome to those of the available alternatives such that it can never be morally wrong for her to act so as to bring about the outcome that she has most reason to want to obtain’ (p. 5). Some might not even recognize this as an aspect of classical act-utilitarianism: There is no mention of maximizing the amount of value in the world, or of value at all. Nonetheless, Portmore argues that this compelling idea is entailed by the conjunction of (i) moral rationalism – ‘the view that agents can be morally required to do only what they have decisive reason to do, all things considered’ (p. 25) – and (ii) his teleological conception of practical reasons (a view defended in chapter 3). Thus, Portmore believes that the true (or most plausible) moral theory must be some form of consequentialism. Portmore dedicates himself to the theoretical motivation, careful formulation and then limited but substantial defence of what he believes to be the most plausible form of consequentialism, a theory that aligns itself with rationality (in the sense that anything morally required by the view is rationally required as well) and is consonant with common-sense morality in general.

Arguments against classical act-utilitarianism spark the dialectic. Act-utilitarianism should be rejected, Portmore argues, because it does not align well with moral rationalism: in many choice situations, we have most reason (all things considered) to act contrary to utilitarianism's requirements. Why? Because act-utilitarianism is insensitive to a variety of morally relevant phenomena, including the reason you have to give priority both to your own welfare and to the welfare of those whom you love most, the reason you have to respect your partner's autonomy, the reason you have to give priority to society's worst-off, and the reason you have to give priority to the deserving over the undeserving (p. 31). Portmore's preferred consequentialist theory – common-sense consequentialism – embraces each of these phenomena as morally relevant.

Traditional consequentialists might question some of Portmore's reasoning here. While some consider various objections from justice against act-utilitarianism damaging, many will not deem the preservation of others’ autonomy or a priority of one's own interests and the interests of one's kin (or loved ones) as factors relevant to what we morally ought to do. For example, I am inclined to believe that a priority of my own interests over others is morally justified only if I am more deserving than those others, or if I contribute more to the world than they do; likewise concerning my kin. Nonetheless, Portmore's arguments against act-utilitarianism are convincing, and the phenomena to which he appeals seem to be at one with common-sense morality.

Chapter 2 is dedicated to a defence of moral rationalism and an explanation of why all moral requirements are rational requirements, providing a sort of metaethical justification for the theorizing to come in chapters 5, 6, and 7. Controversially, Portmore argues that non-moral reasons – primarily, the reasons an agent has to prefer certain outcomes because her own personal welfare is enhanced or diminished in them (reasons of pure self-interest) – can sometimes counter our moral reasons for preferring other outcomes, preventing those moral reasons from generating moral requirements:

Some might balk at the thought that an agent's welfare status in various outcomes is not a moral reason for her preferring or failing to prefer such outcomes. Certainly classical consequentialists like John Stuart Mill will! Traditionalists think along these lines: if the enhancement of others’ welfare is a moral reason for pursuing certain lines of action, then why is not the enhancement of my own welfare a moral reason as well? Why the asymmetry? Portmore argues that reasons for enhancing one's own welfare are rational, non-moral reasons because a person is morally permitted to forgo opportunities to enhance her own welfare even when there is nothing else at stake. So if someone is offered the chance to enjoy a wonderfully pleasant evening – the evening of a lifetime perhaps – but opts to stay home instead, her action might be deemed irrational or imprudent but not immoral, so long as nothing (else?) of moral importance is at stake (p. 129). Some might be inclined to think she has done morally wrong by herself, that she has failed herself from a moral perspective. Regardless, Portmore's distinction between moral and non-moral (but morally relevant) reasons provides a theoretical basis for rich analyses (in chapters 4 and 5) of a variety of phenomena embraced by his common-sense consequentialism: agent-sacrificing options, the self–other asymmetry, supererogatory action, agent-centered options and agent-centered restrictions.

Chapter 3 constitutes a defence of Portmore's teleological conception of practical reasons. Here he defends a view of practical rationality that eschews the concepts of value and desirability in favour of the concept of what an agent has more reason to desire.

Chapters 4 and 5 mark the first steps in Portmore's march to the formulation and defence of common-sense consequentialism. Portmore illustrates how a variety of traditional deontological constraints and various features of common-sense morality can be consequentialized, or accommodated seamlessly by a consequentialist moral theory. He shows how consequentialist theories can accommodate more than just the phenomena mentioned above, but moral dilemmas and special obligations (such as obligations to refrain from murder and to care for one's children) as well. In fact, Portmore argues that consequentialist moral theories do a better job of ‘accounting for our considered moral convictions than even some nonconsequentialist theories can’ (p. 103), including certain rights-based deontologies.

Portmore then introduces and explains a meta-criterion of moral rightness, its motivation derived from the way moral and non-moral reasons combine to generate (or fail to generate) moral requirements and options. A proto-version of Portmore's ultimate view (Schefflerian utilitarianism) is developed and defended – a non-maximizing, dual-ranking consequentialist theory sharing many implications with common-sense morality.

An exploration of imperfect reasons for action (analogues of imperfect duties), the nature of moral options and controversies regarding the nature of the fundamental bearers of normative status transpires in chapter 6, plunging readers into the actualist–possibilist disputes in consequentialist thought. Portmore promotes a novel view here – rational securitism – arguing it to be theoretically superior to both its traditional actualist and possibilist competitors. Securitism is a new species of actualism, because it entails that an agent's future immoral actions in either the actual world or nearby ‘would be’ worlds can determine – in part – what is rationally (and subsequently morally) required of the agent at the present. So – for example – in a wide range of cases, securitism entails that lazy, selfish and procrastinating people are rationally (and morally) excused from committing themselves to various morally attractive lines of action if their future selves simply will not follow through with such commitments just because they would rather not expend the extra effort to do so, even though they can. Possibilists – those who believe we are always morally required to do the best we can – will not be moved, despite the argumentation provided in chapter 7.

The final chapter sees the full formulation and defence of Portmore's novel moral theory: common-sense consequentialism. Its breadth and complexity are too vast to explore here, but hopefully some of its flavour has surfaced in this review.

Common-sense Consequentialism is an impressive, ambitious book – a welcome addition to the literature, especially given recent anti-consequentialist trends. Even devout non-consequentialists will be intrigued by much of it. Portmore's clarity of exposition, rigorous argumentation and dialectical prowess provide for an engaging philosophical encounter, as do the vast range of topics in moral philosophy he investigates. Portmore's thoughtful, earnest, responsible and occasionally provocative nature shines throughout the book.

Of course, common-sense consequentialism will face objections from every angle. In addition to those sketched above, deontologists and virtue ethicists will question the success of his consequentializing efforts in chapter 4. Traditional consequentialists will be hesitant to endorse a theory implying that there is something more to the wrongness of violating a special obligation (to refrain from murder, or to care for one's children) than its disutility (or its depriving the world of value), which are factors usually utilized by consequentialists to explain why it is generally wrong to perform certain kinds of action. Nonetheless, Portmore provides a theoretical infrastructure for a range of consequentialist moral theories (and metaethical justifications thereof) that accommodate the dictates of common-sense morality to various degrees. Interested theorists will be exposed to a spectrum of attractive consequentialist theories for consideration. After all, if Portmore is right, then there might be a consequentialist moral theory for everyone.