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Can the Sciences Help Us to Make Wise Ethical Judgments?


Paul Kurtz

Skeptical Inquirer Volume 28.5, September / October 2004

Scientific knowledge has a vital, if limited, role to play in shaping our moral values and helping us to frame wiser judgments. Ethical values are natural and open to examination in the light of evidence and reason.


Can science and reason be used to develop ethical judgments? Many theists claim that without religious foundations, “anything goes,” and social chaos will ensue. Scientific naturalists believe that secular societies already have developed responsible ethical norms and that science and reason have helped us to solve moral dilemmas. How and in what sense this occurs are vital issues that need to be discussed in contemporary society, for this may very well be the hottest issue of the twenty-first century.

Dramatic breakthroughs on the frontiers of science provide new powers to humans, but they also pose perplexing moral quandaries. Should we use or limit these scientific discoveries, such as the cloning of humans? Much of this research is banned in the United States and restricted in Canada. Should scientists be permitted to reproduce humans by cloning (as we now do with animals), or is this too dangerous? Should we be allowed to make “designer babies?” Many theologians and politicians are horrified by this; many scientists and philosophers believe that it is not only inevitable but justifiable under certain conditions. There were loud cries against in vitro fertilization, or artificial insemination, only two generations ago, but the procedure proved to be a great boon to childless couples. Many religious conservatives are opposed to therapeutic stem-cell research on fetal tissues, because they think that “ensoulment” occurs with the first division of cells. Scientists are appalled by this censorship of scientific research, since the research has the potential to cure many illnesses; they believe those who oppose it have ignored the welfare of countless numbers of human beings. There are other equally controversial issues on the frontiers of science: Organ transplants-who should get them and why? Is the use of animal organs to supply parts for human bodies wrong? Is transhumanism reforming what it means to be human? How shall we control AIDS-is it wicked to use condoms, as some religious conservatives think, or should this be a high priority in Africa and elsewhere? Does global warming mean we need a radical transformation of industry in affluent countries? Is homosexuality genetic, and if so, is the denial of same-sex marriage morally wrong? How can we decide such questions? What criteria may we draw upon?


Many adhere today to the view that ethical choices are merely relativistic and subjective, expressing tastes; and you cannot disputes tastes (de gustibus non disputandum est). If they are emotive at root, no set of values is better than any other. If there is a conflict, then the best option is to persuade others to accept our moral attitudes, to convert them to our moral feelings, or, if this fails, to resort to force.

Classical skeptics denied the validity of all knowledge, including ethical knowledge. The logical positivists earlier in the twentieth century made a distinction between fact, the appropriate realm of science, and value, the realm of expressive discourse and imperatives, claiming that though we can resolve descriptive and theoretical questions by using the methods of science, we cannot use science to adjudicate moral disputes. Most recently, postmodernists, following the German philosopher Heidegger and his French followers, have gone further in their skepticism, denying that there is any special validity to humanistic ethics or indeed to science itself. They say that science is merely one mythological construct among others. They insist that there are no objective epistemological standards; that gender, race, class, or cultural biases likewise infect our ethical programs and any narratives of social emancipation that we may propose. Who is to say that one normative viewpoint is any better than any other, they demand. Thus have many disciples of multicultural relativism and subjectivism often given up in despair, becoming nihilists or cynics. Interestingly, most of these well-intentioned folk hold passionate moral and political convictions, but when pushed to the wall, will they concede that their own epistemological and moral recommendations likewise express only their own personal preferences?

The problem with this position is apparent, for it is impaled on one horn of a dilemma, and the consequence of this option is difficult to accept. If it is the case that there are no ethical standards, then who can say that the Nazi Holocaust and the Rwandan, Cambodian, or Armenian genocides are evil? Is it only a question of taste that divides sadists and masochists on one side from all the rest on the other? Are slavery, the repression of women, the degradation of the environment by profit-hungry corporations, or the killing of handicapped people morally impermissible, if there are no reliable normative standards? If we accept cultural relativity as our guide, then we have no grounds to object to Muslim law (sharia), which condones the stoning to death of adulteresses.


What is the position of those who wish to draw upon science and reason to formulate ethical judgment? Is it possible to bridge the gap and recognize that values are relative to human interests yet allow that they are open to some objective criticisms? I submit that it is, and that upon reflection, most educated people would accept them. I choose to call this third position “objective relativism” or “objective contextualism"; namely, values are related to human interests, needs, desires, and passions-whether individual or socio-cultural-but they are nonetheless open to scientific evaluation. By this, I mean a form of reflective intelligence that applies to questions of principles and values and that is open to modification of them in the light of criticism. In other words, there is a Tree of Knowledge of Good and Evil, which bears fruit, and which, if eaten and digested, can impart to us moral knowledge and wisdom.

In what sense can scientific inquiry help us to make moral choices? My answer to that is it does so all the time. This is especially the case with the applied sciences: medicine, dentistry, nursing, pharmacology, psychiatry, and social psychology; and also in the policy sciences: economics, education, political science; and such interdisciplinary fields as criminology, gerontology, etc. Modern society could not function without the advice drawn from these fields of knowledge, which make evaluative judgments and recommend prescriptions. They advise what we ought to do on a contextual basis.

Nonetheless, there are the skeptical critics of this position, who deny that science per se can help us or that naturalistic ethics is possible. I think that those critics are likewise mistaken and that naturalism is directly relevant to ethics. My thesis is that an increase in knowledge can help us to make wiser decisions. By knowledge, I do not refer simply to philosophical analysis but scientific evidence. It would answer both the religionist, who insists that you cannot be moral unless you are religious, and the subjectivist, who denies there is any such thing as ethical knowledge or wisdom.

Before I outline this position, let me concede that the skeptical philosophical objections to deriving ethics from science have some merit. Basically, what are they? The critics assert that we cannot deduce ethics from science, i.e., what ought to be the case from what is the case. A whole series of philosophers from David Hume to the emotivists have pointed out this fallacy. G.E. Moore, at the beginning of the twentieth century, characterized this as “the naturalistic fallacy” [1] (mistakenly, I think).

But they are essentially correct. The fact that science discovers that something is the case factually does not make it ipso facto good or right. To illustrate: (a) Charles Darwin noted the role of natural selection and the struggle for survival as key ingredients in the evolution of species. Should we conclude, therefore, as Herbert Spencer did, that laissez-faire doctrines ought to apply, that we ought to allow nature to take its course and not help the handicapped or the poorer classes? (b) Eugenicists concluded earlier in the century that some people are brighter and more talented than others. Does this justify an elitist hierarchical society in which only the best rule or eugenic methods of reproduction be followed? This was widely held by many liberals until the fascists began applying it in Germany with dire consequences.

There have been abundant illustrations of pseudoscientific theories-monocausal theories of human behavior that were hailed as “scientific"-that have been applied with disastrous results. Examples: (a) The racial theories of Chamberlain and Gobineau alleging Aryan superiority led to genocide by the Nazis. (b) Many racists today point to IQ to justify a menial role for blacks in society and their opposition to affirmative action. (c) The dialectical interpretation of history was taken as “scientific” by Marxists and used to justify class warfare. (d) Environmentalists decried genetics as “racist” and thought that changes in species should only be induced by modifications of the environment. Thus, one has to be cautious about applying the latest scientific fad to social policy.

We ought not to consider scientific specialists to be especially gifted or possessed with ethical knowledge nor empower them to apply this knowledge to society-as B.F. Skinner in Walden II and other utopianists have attempted to do. Neither scientist-kings nor philosopher-kings should be entrusted to design a better world. We have learned the risks and dangers of abandoning democracy to those wishing to create a Brave New World. Alas, all humans-including scientists-are fallible, and excessive power may corrupt human judgment. Given these caveats, I nevertheless hold that scientific knowledge has a vital, if limited, role to play in shaping our moral values and helping us to frame wiser judgments of practice--surely more, I would add, than our current reliance on theologians, politicians, military pundits, corporate CEOs, and celebrities!


How and in what sense can scientific inquiry help us?

I wish to present a modified form of naturalistic ethics. By this, I mean that ethical values are natural; they grow out of and fulfill human purposes, interests, desires, and needs. They are forms of preferential behavior evinced in human life. “Good,” “bad,” “right,” and “wrong” relate to sentient beings, whether human or otherwise. These values do not reside in a far-off heaven, nor are they deeply embedded in the hidden recesses of reality; they are empirical phenomena.

The principle of naturalism is based on a key methodological criterion: We ought to consider our moral principles and values, like other beliefs, open to examination in the light of evidence and reason and hence amenable to modification.

We are all born into a sociocultural context; and we imbibe the values passed on to us, inculcated by our peers, parents, teachers, leaders, and colleagues in the community.

I submit that ethical values should be amenable to inquiry. We need to ask, are they reliable? How do they stack up comparatively? Have they been tested in practice? Are they consistent? Many people seek to protect them as inviolable truths, immune to inquiry. This is particularly true of transcendental values based on religious faith and supported by custom and tradition. In this sense, ethical inquiry is similar to other forms of scientific inquiry. We should not presuppose that what we have inherited is true and beyond question. But where do we begin our inquiry? My response is, in the midst of life itself, focused on the practical problems, the concrete dilemmas, and contextual quandaries that we confront.

Let me illustrate by refer to three dilemmas. I do so not in order to solve them but to point out a method of inquiry in ethics. First, should we exact the death penalty for people convicted of murder? The United States is the only major democracy that still demands capital punishment. What is the argument for the death penalty? It rests on two basic premises: (a) A factual question is at issue: capital punishment is effective in deterring crime, especially murder; and (b) the principle of justice that applies is retributive. As the Old Testament adage reads, “Whatever hurt is done, you shall give life for life, eye for eye, tooth for tooth. . . .” [2]

The first factual premise can be resolved by sociological studies, by comparing the incidence of murder in those states and nations that have the death penalty in force and those that do not and by states and nations before and after the enactment or abrogation of the death penalty. We ask, has there been an increase or a decrease in murder? If, as a matter of fact, the death penalty does not restrain or inhibit murder, would a person still hold his view that the death penalty ought to be retained? The evidence suggests that the death penalty does not to any significant extent reduce the murder rate, especially since most acts of murder are not deliberate but due to passion or are an unexpected result of another crime, such as robbery. Thus, if one bases his or her belief in capital punishment primarily on the deterrence factor, and it does not deter, would one change one’s belief? The same consideration should apply to those who are opposed to the death penalty: Would they change their belief if they thought it would deter excessive murder rates? These are empirical questions at issue. And the test of a policy are its consequences in the real world. Does it achieve what it sets out to do?

There are, of course, other factual considerations, such as: Are many innocent people convicted of crimes they did not commit (as was recently concluded in the State of Illinois)? Is capital punishment unfairly applied primarily to minorities? This points to the fact that belief in capital punishment is, to some extent, a function of scientific knowledge concerning the facts of the case. This often means that such measures should not be left to politicians or jurors alone to decide; the scientific facts of the case are directly relevant.

The second moral principle of retributive justice is far more difficult to deal with, for this may be rooted in religious conviction or in a deep-seated tribal sense of retaliation. If you injure my kin, it is said, I can injure yours; and this is not purely a factual issue. There are other principles of justice that are immediately thrown into consideration. Those opposed to the death penalty say that society “should set a humane tone and not itself resort to killing.” Or again, the purpose of justice should be to protect the community from future crimes, and alternative forms of punishment, perhaps lifetime imprisonment without the right of parole, might suffice to deter crime. Still another principle of justice is relevant: Should we attempt, where possible, to rehabilitate the offender? All of the above principles are open to debate. The point is, we should not block inquiry; we should not say that some moral principles are beyond any kind of re-evaluation or modification. Here, a process of deliberation enters in, and a kind of moral knowledge emerges about what is comparatively the best policy to adopt.

Another example of the methods of resolving moral disputes is the argument for assisted suicide in terminal cases, in which people are suffering intolerable pain. This has become a central issue in the field of medical ethics, where medical science is able to keep people alive who might normally die. I first saw the emergence of this field thirty years ago, when I sponsored a conference in biomedical ethics at my university and could find very few, if any, scholars or scientists who had thought about the questions or were qualified experts. Today, it is an essential area in medicine. The doctor is no longer taken as a patriarchal figure. His or her judgments need to be critically examined, and others within the community, especially patients, need to be consulted. There are here, of course, many factual questions at issue: Is the illness genuinely terminal? Is there great suffering? Is the patient competent in expressing his or her long-standing convictions regarding his or her right to die with dignity? Are there medical and legal safeguards to protect this system against abuse?

Our decision depends on several further ethical principles: (a) the informed consent of patients in deciding whether they wish treatment to continue; (b) the right of privacy, including the right of individuals to have control of their own bodies and health; and (c) the criterion of the quality of life.

One problem we encounter in this area is the role, again, of transcendental principles. Some people insist, “God alone should decide life-and-death questions, not humans.” This principle, when invoked, is beyond examination, and for many people it is final. Passive euthanasia means that we will not use extraordinary methods to keep a person alive, where there is a longstanding intent expressed in a living will not to do so. Active euthanasia will, under certain conditions, allow the patient, in consultation with his physician, to hasten the dying process (as practiced in Oregon and the Netherlands). The point is, there is an interweaving of factual considerations with ethical principles, and these may be modified in the light of inquiry, by comparing alternatives and examining consequences in each concrete case.

I wish to illustrate this process again by referring to another issue that is hotly debated today: Should all cloning research be banned? The Canadian legislature, in March 2004, passed legislation that will put severe restrictions on such scientific research. The bill is called “An Act Respecting Assisted Human Reproduction” (known as C-56), and it makes it a criminal offense to engage in therapeutic cloning, to maintain an embryo outside a woman’s body for more than fourteen days, to genetically manipulate embryos, to choose the gender of offspring, to sell human eggs and sperm, or to engage in commercial surrogacy. It also requires that in vitro embryos be created only for the purpose of creating human beings or for improving assisted human-reproductive procedures. Similar legislation was passed by the U.S. House of Representatives and is before the Senate. It is still being heatedly debated. It includes the prohibition of reproductive cloning as well as therapeutic stem-cell research. Two arguments against reproductive cloning are as follows: (a) It may be unsafe (at the present stage of medical technology) and infants born may be defective. This factual objection has some merit. (b) There is also a moral objection saying that we should not seek to design children. Yet we do so all the time, with artificial insemination, in vitro fertilization, and surrogate motherhood. We already are involved in “designer-baby” technology, with amniocentesis, pre-implantation, genetic testing, and chorionic villus sampling (the avoiding of unwanted genes by aborting fetuses and implanting desirable embryos).

If it were to become safe, would reproductive cloning become permissible? I can think of situations where we might find it acceptable-for example, if couples are unable to conceive by normal methods.

It is the second area I mentioned above that is especially telling-the opposition to any forms of embryonic stem-cell research. Proponents maintain that this line of research may lead to enormous benefits by curing a wide range of diseases such as Parkinson’s disease, Alzheimer’s, or juvenile diabetes. Adult stem cells are now being used, but embryonic stem cells may provide important new materials. The criterion here is consequential: that positive outcomes may result. Opponents maintain that this type of research is “immoral” because it is tampering with human persons possessed of souls. Under this interpretation, “ensoulment” occurs at the moment of conception. This is said to apply to embryos, many of which, however, are products of miscarriages or abortions. Does it also apply once the division of stem cells occurs? Surely a small collection of cells, which is called a blastocyst, is not a person, a sentient being, or a moral agent prior to implantation. Leon Kass, chair of President Bush’s Council on Bioethics, believes that human life cannot be treated as a commodity and it is evil to manufacture life. He maintains that all human life, including a cloned embryo, has the same moral status and dignity as a person from the moment of conception.

This controversy pits two opposing moral claims: (a) the view that stem-cell research may be beneficent because of its possible contributions to human health (i.e., it might eliminate debilitating diseases) versus (b) an ethic of revulsion against tampering with natural reproductive processes. At issue here are the questions of whether ensoulment makes any sense in biology and whether personhood can be said to have begun at such an early stage, basically a transcendental claim that naturalists object to on empirical grounds. These arguments are familiar in the abortion debate; it would be unfortunate if they could be used to censor scientific stem-cell research.

This issue is especially relevant today, for transhumanists say that we are discovering new powers every day that modify human nature, enhance human capacities, and extend life spans. We may be able to extend memory and increase human perception and intelligence dramatically by silicon implants. Traditionalists recoil in horror, saying that post-humanists would have us transgress human nature. We would become cyborgs.

But we already are, to some extent: we wear false teeth, eyeglasses, and hearing aids; we have hair grafts, pacemakers, organ transplants, artificial limbs, and sex-change/sexual reassignment operations and injections; we use Viagra to enhance sexual potency or mega-vitamins and hormone therapy. Why not go further? Each advance raises ethical issues: Do we have the reproductive freedom and responsibility to design our children by knowing possible genetic disorders and correcting them before reproduction or birth?


This leads to an important distinction between two kinds of values within human experience. Let me suggest two possible sources: (a) values rooted in unexamined feelings, faith, custom, or authority, held as deep-seated convictions beyond question, and (b) values that are influenced by cognition and informed by rational inquiry.

Naturalists say that scientific inquiry enables us to revise our values, if need be, and to develop, where appropriate, new ones. We already possess a body of prescriptive judgments that have been tested in practice in the applied sciences of medicine, psychiatry, engineering, educational counseling, and other fields. Similarly, I submit that there is a body of prescriptive ethical judgments that has been tested in practice and that constitutes normative knowledge; and new normative prescriptions are introduced all the time as the sciences progress.

The question is thus raised, what criteria should we use to make ethical choices? This issue is especially pertinent today for those living in pluralistic societies such as ours, where there is diversity of values and principles.

In formulating ethical judgments, we need to refer to what I have called a “valuational base.” [3] Packed into this referent are the pre-existing de facto values and principles that we are committed to; but we also need to consider empirical data, means-ends relationships, causal knowledge, and the consequences of various courses of action. It is inquiry that is the instrument by which we decide what we ought to do and that we should develop in the young. We need to focus on moral education for children; we wish to structure positive traits of character and also the capacity for making reflective decisions. There are no easy recipes or simple formulae that we can appeal to, telling us what we ought to do in every case. There are, however, what W.D. Ross called prima facie general principles of right conduct, the common moral decencies, a list of virtues, precepts, and prescriptions, ethical excellences, obligations, and responsibilities, which are intrinsic to our social roles. But how they work out in practice depends on the context at hand, and the most reliable guide for mature persons is cognitive inquiry and deliberation.

Conservative theists have often objected to this approach to morality as dangerous, given to “debauchery” and “immorality.” Here, there is a contrast between two different senses of morality: (a) the obedience/authoritarian model, in which humans are expected to follow moral absolutes derived from ancient creeds, and (b) the encouragement of moral growth, implying that there are within the human species potential moral tendencies and cognitive capacities that can help us to frame judgments.

For a naturalistic approach, in the last analysis, ethics is a product of a long evolutionary process. Evolutionary psychology has pointed out that moral rules have enabled human communities to adapt to threats to their survival. This Darwinian interpretation implies a biological basis for reciprocal behavior- epigenetic rules-according to E.O. Wilson (1998). [4] The social groups that possessed these rules transmitted them to their offspring. Such moral behavior provides a selective advantage. There is accordingly an inward propensity for moral behavior, moral sentiments, empathy, and altruism within the species.

This does not deny that there are at the same time impulses for selfish and aggressive tendencies. It is a mistake, however, to read in a doctrine of “original sin” and to say that human beings are by nature sinful and corrupt. I grant that there are individuals who lack moral empathy; they are morally handicapped. Some may even be sociopaths. The salient point is that there are genetic potentialities for good and evil; but how they work out and whether beneficent behavior prevails is dependent on cultural conditions. Both our genes (genetics) and memes (social patterns of enculturation) are factors that determine how and why we behave the way we do. We cannot simply deduce from the evolutionary process what we ought to do. What we do depends in part upon the choices we make. Thus, we still have some capacity for free choice. Though we are conditioned by environmental and biogenetic determinants, we are still capable of cognitive processes of selection, and rationality and intentionality play a causative role. (Note: There is a considerable scientific literature that supports this evolutionary view. See Daniel Dennett, Freedom Evolves [New York: Viking, 2003] and Darwin’s Dangerous Idea [New York: Simon and Schuster, 1995]; Brian Skyrm, Evolution of the Social Contract [Cambridge: Cambridge University Press, 1996], Robert Wright, The Moral Animal [New York: Pantheon Books, 1994] and Nonzero [New York: Vintage Books, 2001], Matt Ridley, The Origins of Virtue [New York: Viking, 1996], and Elliott Sober and David Sloan Wilson, Unto Others [Cambridge, Massachusetts: Harvard University Press, 1998].)

Ethical precepts need not be based upon transcendental grounds or dependent upon religious faith. Undoubtedly, the belief that they are sacred may strengthen moral duties for many persons, but it is not necessary for everyone.

I submit that it is time for scientists to recognize that they have an opportunity to contribute to naturalistic ethics. We stand at an interesting time in human history. We have great power to ameliorate the human condition. Biogenetic engineering, nanotechnology, and space research open new opportunities for humankind to create a better world.

Yet there are those today who wish to abandon human reason and freedom and return to mythological legends of our premodern existence, including their impulses of aggres- sion and self-righteous vengeance. I submit that the Enlightenment is a beacon whose promise has not been fulfilled and that humankind needs to accept the responsibility for its own future.


A caveat is in order. In the last analysis, some degree of skepticism is a necessary antidote to all forms of moral dogmatism. We are continually surrounded by self-righteous moralists who claim that they have the Absolute Truth, Moral Virtue, or Piety or know the secret path to salvation and wish to impose their convictions on all others. They are puffed up with an inflated sense of their own rectitude as they rail against unbenighted immoral sinners who lack their moral faith. These moral zealots are willing to repress or even sacrifice anyone who stands in their way. They have in the past unleashed conquering armies in the name of God, the Dialectic, Racial Superiority, Posterity, or Imperial Design. Skepticism needs to be applied not only to religious and paranormal fantasies but to other forms of moral and political illusions. These dogmas become especially dangerous when they are appealed to in order to legislate morality and are used by powerful social institutions, such as a state or church or corporation, to enforce a particular brand of moral virtue. Hell hath no fury like the self-righteous moral fanatic scorned.

The best antidote for this is some skepticism and a willingness to engage in ethical inquiry, not only about others' moral zeal, but about our own, especially if we are tempted to translate the results of our own ethical inquiries into commandments. The epistemological theory that I propose is based upon methodological principles of skeptical scientific inquiry, and it has important moral implications. For in recognizing our own fallibility, we thereby can learn to tolerate other human beings and to appreciate their diversity and the plurality of lifestyles. If we are prepared to engage in cooperative ethical inquiry, then perhaps we are better prepared to allow other individuals and groups some measure of liberty to pursue their own preferred lifestyles. If we are able to live and let live, then this can best be achieved in a free and open democratic society. Where we differ, we should try to negotiate our divergent views and perhaps reach common ground; and if this is impractical, we should at least attempt to compromise for the sake of our common interests. The method of ethical inquiry requires some intelligent and informed examination of our own values as well as the values of others. Here we can attempt to modify attitudes by an appeal to cognitive beliefs and to reconstruct them by an examination of the relevant scientific evidence. Such a give-and-take of constructive criticism is essential for a harmonious society. In learning to appreciate different conceptions of the good life, we are able to expand our own dimensions of moral awareness; and this is more apt to lead to a peaceful world.

By this, I surely do not mean to imply that anything and everything can or should be tolerated or that one thing is as good as the next. We should be prepared to criticize moral nonsense parading as virtue. We should not tolerate the intolerable. We have a right to strongly object, if need be, to those values or practices that we think are based on miscalculation, misconception, or that are patently false or harmful. Nonetheless, we might live in a better world if inquiry were to replace faith; deliberation, passionate commitment; and education and persuasion, force and war. We should be aware of the powers of intelligent behavior, but also of the limitations of the human animal and of the need to mitigate the cold, indifferent intellect with the compassionate and empathic heart. Thus, I conclude that within the ethical life, we are capable of developing a body of melioristic principles and values and a method of coping with problems intelligently. When our ethical judgments are based on rational and scientific inquiry, they are more apt to express the highest reaches of excellence and nobility and of civilized human conduct. We are in sore need of that today.


  1. G.E. Moore. Principia Ethica (Cambridge: Cambridge University Press, 1903).
  2. See Exodus 21.
  3. Kurtz, Paul (ed.). The New Skepticism: Inquiry and Reliable Knowledge (Amherst, New York: Prometheus, 1992), chapter 9.
  4. Wilson, E.O. Consilience (New York: Alfred Knopf, 1998).

Paul Kurtz

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Professor Paul Kurtz is the founder of the Center for Inquiry, CFI's former chairman, the former Editor-in-Chief of Free Inquiry magazine, and professor emeritus of philosophy at the State University of New York at Buffalo. Kurtz has spent much of his life on the critical examination of religion, but believes that naturalists need to emphasize and build positive alternatives to religion. For Kurtz, it is not enough to reject God, but to affirm the positive implications of the secular humanist perspective.