Since international relations and factual phenomena can be observed both externally and internally, the factual process of international relations should include two aspects: observing its external behavior and explaining its internal meaning. Here, the proper judgment of the nature of facts requires observation and interpretation of different aspects, which is very important for proper observation and interpretation. If the treatment method is improper, it will lead to a major deviation in the conclusion.

For example, whether Saddam Hussein's regime in Iraq has weapons of mass destruction is a question that needs verification (observation) to confirm, but the United States has the means to interpret false information into conclusions, and thus launched a war. Methodologically, this is a typical counterexample.

The purpose of observing the observable facts is to find out the objective truth of the facts and determine the relationship between variables on this basis. In doing so, researchers must insist on objective observation, that is, seeking truth from facts. The way researchers observe can be summarized as qualitative and quantitative. The case study of war and the judgment of violent conflict or war are qualitative observations, while describing the development of global conflicts according to figures is quantitative observations. In the study of international relations, some facts are more suitable for quantitative observation, but some facts are difficult to measure. For example, people can clearly feel the atmosphere of fear caused by terrorist incidents, but its degree is difficult to make quantitative analysis, because this fact is reflected in people's psychological state.