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The moral views of secular humanism have been subjected to criticism by religious fundamentalist theists. The secular humanist recognizes the central role of morality in human life; indeed, ethics was developed as a branch of human knowledge long before religionists proclaimed their moral systems based upon divine authority. The field of ethics has had a distinguished list of thinkers contributing to its development: from Socrates, Democritus, Aristotle, Epicurus, and Epictetus, to Spinoza, Erasmus, Hume, Voltaire, Kant, Bentham, Mill, G. E. Moore, Bertrand Russell, John Dewey, and others. There is an influential philosophical tradition that maintains that ethics is an autonomous field of inquiry, that ethical judgments can be formulated independently of revealed religion, and that human beings can cultivate practical reason and wisdom and, by its application, achieve lives of virtue and excellence. Moreover, philosophers have emphasized the need to cultivate an appreciation for the requirements of social justice and for an individual's obligations and responsibilities toward others. Thus, secularists deny that morality needs to be deduced from religious belief or that those who do not espouse a religious doctrine are immoral. For secular humanists, ethical conduct is, or should be, judged by critical reason, and their goal is to develop autonomous and responsible individuals, capable of making their own choices in life based upon an understanding of human behavior.
Morality that is not God-based need not be antisocial, subjective, or promiscuous, nor need it lead to the breakdown of moral standards. Although we believe in tolerating diverse lifestyles and social manners, we do not think they are immune to criticism. Nor do we believe that any one church should impose its views of moral virtue and sin, sexual conduct, marriage, divorce, birth control, or abortion, or legislate them for the rest of society. As secular humanists we believe in the central importance of the value of human happiness here and now. We are opposed to absolutist morality, yet we maintain that objective standards emerge, and ethical values and principles may be discovered, in the course of ethical deliberation. Secular humanist ethics maintains that it is possible for human beings to lead meaningful and wholesome lives for themselves and in service to their fellow human beings without the need of religious commandments or the benefit of clergy. There have been any number of distinguished secularists and humanists who have demonstrated moral principles in their personal lives and works: Protagoras, Lucretius, Epicurus, Spinoza, Hume, Thomas Paine, Diderot, Mark Twain, George Eliot, John Stuart Mill, Ernest Renan, Charles Darwin, Thomas Edison, Clarence Darrow, Robert Ingersoll, Gilbert Murray, Albert Schweitzer, Albert Einstein, Max Born, Margaret Sanger, and Bertrand Russell, among others.
We believe that moral development should be cultivated in children and young adults. We do not believe that any particular sect can claim important values as their exclusive property; hence it is the duty of public education to deal with these values. Accordingly, we support moral education in the schools that is designed to develop an appreciation for moral virtues, intelligence, and the building of character. We wish to encourage wherever possible the growth of moral awareness and the capacity for free choice and an understanding of the consequences thereof. We do not think it is moral to baptize infants, to confirm adolescents, or to impose a religious creed on young people before they are able to consent. Although children should learn about the history of religious moral practices, these young minds should not be indoctrinated in a faith before they are mature enough to evaluate the merits for themselves. It should be noted that secular humanism is not so much a specific morality as it is a method for the explanation and discovery of rational moral principles.