The study of cause and effect - which requires a strong grasp of historical chronology - constitutes one of the basic approaches to the discipline of history. The underlying principle is one adapted from physics: for every action there is an equivalent reaction; every cause results in an effect. In historical terms, every event has a cause, and is itself the cause of subsequent events, which may therefore be considered its effect(s), or consequences. For various reasons, three of which are listed below, this view of history has become less popular in recent times. However, thinking in terms of cause and effect remains a valuable skill you should master.

Some of the problems with the cause and effect approach to history include:

1. its risk of reducing complex historical issues to overly simplistic explanations. For example, "in 1914, Austrian Crown Prince Archduke Franz Ferdinand was assassinated in Sarajevo by a Bosnian Serb ['the cause']. In retaliation, Austria declared war on Serbia, launching the sequence of events that culminated in World War I ['the effect']." In fact, both the assassination of Franz Ferdinand and even Austria's declaration of war against Serbia are but two relatively minor variables within the far larger set of complex issues that contributed to the many causes of World War I. While Franz Ferdinand's assassination may have been the immediate catalyst of the war, it was certainly not the cause.
2. its implicit reliance on the negative logic-argument. Part of the way in which physicists (and some philosophers, too) have applied the cause-and-effect model to their subject matter is by way of negative logic. Not only did A cause B, but (here's the negative logic) B would not have happened, had it not been for A. In history, however, things do not work out as neatly. Take the above World War I example. Following the negative logic argument, if Franz Ferdinand hadn't been assassinated (the catalyst for World War I, remember?), the war itself would never have begun. This claim is highly doubtful: most historians agree that the rivalry between the major European empires, the power blocs that had been established among them, and the complex set of alliances that existed within each bloc had made war all but inevitable long before 1914. In fact, if Franz Ferdinand had not been assassinated, and even if Austria had not declared war on Serbia, a major military confrontation involving all European powers would most likely still have occurred.
3. its inability to anticipate the unreliability principle. Another concept from physics, the unreliability (or Heisenberg) principle, articulated in 1927, severely complicated physicists' earlier faith in simple causal relationships with its discovery that, no matter how clearly a cause seems poised to have a certain effect, unexpected variables may impact upon the outcome in unanticipated ways. The same is true of history. For example, the European power blocs of the pre-World War I period and the complex sets of internal non-aggression and mutual aid agreements that existed within them made war inevitable, as outlined above. Following World War II, however, a similar set of circumstances (the U.S.-led NATO alliance vs. the Soviet-led Warsaw Pact, each of which was also internally organized around the principles of mutual aid and non-aggression) did not lead to a direct confrontation between the two blocs. In fact, contrary to popular wisdom, history does not necessarily repeat itself.

Despite the above-listed reservations, you still need to develop an understanding of cause and effect, for two reasons:

1. an awareness of cause and effect, simplistic as it may be, does help you recognize causal relationships between historical events; this is an important skill
2. you will frequently find your history professor assigning essay questions that ask you to "explain the cause(s)" or "examine the effect(s)" of specific events in history.

Like it or not, cause and effect is here to stay.

Here's a sample topic, one that is in keeping with our events-leading-up-to-World-War-II theme, and a favorite in twentieth-century history classes:

This is classic cause and effect, as even implied in the wording of the question: the Treaty of Versailles ("the cause"), dictated by Britain and France in the aftermath of World War I, "contributed" to the rise of Hitler (which, therefore, is "the effect"). In order to fulfill such an assignment, you will first explain the Treaty - which called upon defeated Germany to cede territories, give up its colonies to the victorious Allies, limit its army and navy, and pay war reparations of $33 billion - then show ways in which the treaty's effects (anger and resentment in Germany, accompanied by political and economic turmoil) helped set the scene for the rise of Hitler over the next fifteen years. (See also Establishing a Broader Context on this.)

As you proceed, you will notice a whole series of causes and effects:

Thus we see that the method of cause and effect can yield useful results and, in so doing, can avoid its three above-listed potential pitfalls. By tracing each effect of the treaty in its own right, we are not reducing the complex issue of the rise of Hitler to an overly simplistic cause but - far from it - establishing a broader context within which to understand Hitler's career. Nor are we claiming the negative argument, that, had it not been for the Treaty of Versailles, Hitler would not have come to power (avoid such claims; also the claim that, had it not been for the treaty, there would have been no World War II; there are too many variables involved to make such claims). Finally, we are acknowledging the unpredictability principle: a Treaty that was designed to bring Germany to its knees and render it unfit to ever start another war in fact had an entirely different long-term effect.