Historical determinism

Things are in the saddle, and ride mankind. Historical determinism is the belief that historical, and by extension present and future, events unfold according to predetermined sequences.

Examples
Historical determinism lurks within many belief systems, including:
 * 19th- and some early 20th-century anthropology and archaeology (generally referred to as "cultural evolutionism") - whereby societies evolve through time on a single path from small bands of hunter-gatherers to nation-states resembling those of 19th-century Europe —  and no further.
 * Certain formulations of biological determinism applied to historical processes, e.g. racialist theories that posited that the achievements of European civilization were due to biological superiority. These ideas were often tied into the anthropological theories above.
 * Hegelian dialectics - every development in history (thesis) would lead to a reaction (antithesis). The contrast between both will lead to a reconciliation or otherwise be settled (synthesis), which would eventually become a new thesis, etc. This view had a great influence on...
 * Marxism (and dialectical materialism) - civilization goes through several stages, from primitive communism, through the rise of the state and private property, to feudalism, capitalism, socialism and finally to communism.
 * Dispensationalism - a fundamentalist Protestant Christian belief in seven periods of time or "dispensations" the earth has gone through and will go through; according to this belief we are currently in the "dispensation of grace" and will be until the rapture happens.
 * Oswald Spengler's The Decline of the West, arguably an intellectual influence on Nazism (...if there was anything intellectual about them, which is doubtful), claimed a civilization model in which each civilization necessarily passes through several epochs and eventually declines. He never said though which was the equivalent of the Nazis in other civilisations.
 * Auguste Comte's positivism - in his famous Law of the Three Stages Comte postulated that all human societies would pass through three stages: the religious stage, the metaphysical stage and the positive stage. He believed that his own philosophy kicked off the third stage.
 * Psychohistory (in the non-Asimov use of the term) - Many of its works tie childrearing practices to the outbreak of war, and said practices are claimed to evolve in five stages from infanticide to something resembling a Benjamin Spock book.
 * Futurism - Many works of technological determinism may be found under this heading. Current incarnations appear in the form of "transhumanism" and "singularitarianism".

Historicism
Historical determinism was especially popular during the 19th century when it was known as historicism. Basically, historicism is a historian's scientism. Historicists attempted to get the study of human history to become a natural, 'hard' science. They typically identified a 'motor' behind all human history (class struggle, national mission, racial destiny, reason, violence, or ).

In almost all cases, this motor is presented a single, all-encompassing "magic bullet" that is held to control and explain everything in society, no matter how tenuous and convoluted the connection. ("If all you have is a hammer, everything looks like a nail.")

It is worth noting:
 * This motor, whatever it may be, is usually assigned such traditionally divine qualities as omnipotent will, ineffability, and ineluctability.
 * Adherents are generally expected to submit to and enforce the will of God History.
 * Adherents tend to interpret their own will as the will of God History; just like God, History has a way of telling the people it speaks to exactly what they want to hear.

Soooo ... does this remind you of anything?

By careful study of the workings of the motor during human history, most historicists believed it could be used to predict the future, which if successful would in effect turn history into a natural science. Eventually, these attempts failed, as it turned out human behavior is not as predictable as most historicists believed it is. It has sometimes been argued that much of the nasty cataclysm of war and violence of the 20th century was caused by failed attempts to forcefully have reality fit the perpetrator's pet historicist theory.

Notably, most historicists were not historians (Comte, Marx, and Hegel were philosophers) and historians have generally been aware that their field of study is distant from the natural sciences. This is in stark contrast with practitioners of many other social sciences. What sets history apart from both the natural and social sciences is that it looks for the unique rather than the general. Many historians (though there are exceptions) have been plainly not interested in formulating general laws about human history.

Historical determinism and historicism were decisively rebutted by Karl Popper, who argued that it is impossible to predict the future course of history. His argument goes like this:
 * The biggest historical changes in recent history have for the most part been caused by technological changes. If you could get somebody who lived a hundred years ago to time travel to the present the most striking differences would probably be technological ones, and even if that is not the case many of the social, cultural and political changes can at least in part be ascribed to changes in technology.
 * Technological progress depends heavily on scientific progress.
 * Therefore, in order to predict the future, one should be able to predict future scientific knowledge.
 * It is, however, not possible to predict future scientific knowledge. You can't predict a scientific fact that has not been discovered yet. If you could, it would not be a future discovery but a current one. In other words, if you know a fact that is not yet known, you know it now, so it's not a prediction any more. Knowing things you don't know yet is an impossible logical contradiction.
 * Therefore, it is not possible to predict the future course of history.

Many theories espousing historical determinism could be considered as scientific hypotheses that were initially valid but eventually failed. Continued adherence to such theories, however, should be classified as pseudoscience. Many historical determinists will tell you that the revolution or the rapture is still going to happen, but at some undetermined point in the future. Although they do make a prediction, it is not a testable one, making it impossible to falsify, making it essentially worthless for scientific purposes.

Modern variants
Since the late 20th century there has been a renewed interest in bringing history and natural science closer to each other. Although some have tried to formulate laws about human history, these attempts have stayed short of complete determinism.

One example is Richard Dawkins' The Selfish Gene, presenting a gene-centered view of evolution, leading some historians to adopt a gene-centered view of history. More relevant is Guns, Germs, and Steel, which explores the different ways human societies developed, and especially why some became powerful and ended up ruling the world while others didn't, based on differences in natural geography. Again, notably, neither Dawkins (a biologist) nor Diamond (a geographer) is a historian.

There are however two important differences that distinguish Dawkins and Diamond from their 19th-century counterparts. The first difference is that the modern authors don't just make up a theory and declare it to be scientific, but rather start out with accepted scientific theories and work out from there. Although one might disagree with the implications those theories have on human history, few people would argue that evolutionary biology or physical geography are unscientific.

Secondly, unlike the 19th-century historical determinists the modern 'determinists' do not claim to be able to predict the future. When they do make testable predictions it is about events that already happened. Diamond, for example, argues that when two previously isolated societies encounter each other, the one with a superior biological (nutritional) package will eventually prevail, as happened for example when the Europeans conquered the Americas.