Pinker's project is to explain why violence has declined and human life has improved. I've read elsewhere that he rules out biological evolutionary change thus far in our history; in any case, he states in the first few pages that his focus is environmental. Here is, in a couple of stages, his topic statement:
[The decline of violence] is a collection of statistical trends in the behavior of groups of humans in various epochs, and as such it calls for an explanation in terms of psychology and history: how human minds deal with changing circumstances (location 170)... The way to explain the decline of violence is to identify the changes in our cultural and material milieu that have given our peaceable motives the upper hand (179).If you accept the factual premise that violence of all kinds has declined at an accelerating pace, the moral premise that this change is a the most important fact in human social history, and the historical/scientific premise that the decline can be explained by "changes in our cultural and material milieu", then you must reject originalism in all its forms. No codification of human wisdom, or of alleged divine wisdom, is a permanent guide to human affairs, because human ethical and moral understanding not only change constantly but improve over time. Hence Pinker cites as a factor driving the accelerated diminution of violence in the last sixty years new ethical principles that have gained/are gaining force of law in the developed world:
Finally, the postwar era, symbolically inaugurated by the Universal Declaration of Human Rights in 1948, has seen a growing revulsion against aggression on smaller scales, includng violence against ethnic minorities, women, children, homosexuals, and animals. These spin-offs from the concept of human rights--civil rights, women's rights, children's rights, gay rights, and animal rights--were asserted in a cascade of movements from the late 1950s to the present day which I will call the Rights Revolutions (location 213).All societies need "conservative" brakes, because human innovations err in multiple directions, and real improvements in moral understanding and social and political organization need time to manifest themselves as such and so achieve practical consensus. But all societies also need mechanisms to foster moral and social innovations and codify those that prove their power to improve human life. We need, that is, the freedom to recognize that we are in crucial ways superior to the founding fathers of our religions and polities (partly because they historically have almost always been fathers, not mothers -- Pinker names "feminization" as an important recent factor in the decrease of violence). Not only can't we know what the founding fathers of the United States would have thought of Roosevelt's Four Freedoms or Social Security or universal healthcare or assault weapons bans (no doubt they would have been fiercely divided). It doesn't matter what they would have thought. They are not here to judge; if they were, they would be different people.
More generally, while all humans err, and Jesus or Thomas Jefferson might in some cases be right where Franklin or Eleanor Roosevelt or Mahatma Gandhi or Nelson Mandela are wrong, the ethics and rules of governance expressed in the legal codes of the developed world and multilateral institutions build on are superior to those of the Tanach, the New Testament, the Talmud, The Koran, the Magna Carta, and the United States Constitution. This is less true of the last, in that the Constitution can be amended, albeit with great difficulty. And the obsolescence of old guides generally is mitigated to the extent that all scriptures and codas are irrepressibly "amended" via interpretation -- itself often codified. Modern secular law self-amends by judicial rulings accorded precedential authority, perhaps our best means to date of regulating necessary interpretive change. But in my view, those texts to which tradition allows no explicit emendations are more fetters than they are aids to further progress. We are better off recognizing their historic role in shaping our current values than we are investing them with authority.
UPDATE: perhaps this early-onset blogging really is rather foolish. I just finished Pinker's first chapter, which is a brief history of violence. Pinker plainly not only thinks that past moral codes, including scriptures, should not be our guides today; he asserts that no one does follow them. If they did, we'd have to incarcerate them, so swiftly is the range of acceptable violence being restricted. Pinker:
In recent millennia and centuries the Bible has been spin-doctored, allegorized, superseded by less violent texts (the Talmud among Jews and teh New Testament among Christians), or discreetly ignored. And that is the point. Sensibilities toward violence have changed so much that religious people today compartmentalize their attitude to the Bible. they pay it lip service as a symbol of morality, while getting their actual morality from more modern principles (Location 542).