The historical sciences are related to other sciences, and all sciences share the same basic goals and methods.

Scientific Methods in Historical Sciences

For most scientists, the main goal of science is to find truth. They want to construct theories that are true, that correspond with reality by correctly describing what really happens in nature. In a search for true theories, the main thinking tools — the generation and evaluation of theories, using observation, imagination, and logic — are described in an introduction to The Simple Logic of Scientific Method and in this brief summary from it:

As shown in the diagram below, OBSERVATIONS (from physical experiments) are used to imaginatively generate a THEORY, which can be used with if-then logic (in a mental experiment) to make PREDICTIONS, so you can do a REALITY CHECK by comparing observations with predictions, to test whether "the way you think it is" (by assuming the theory is true) corresponds to "the way it really is."

Is there a scientific method? If "method" means "a single method, used in the same way by all scientists at all times," the answer is NO, so we should not talk about The Scientific Method.
Are there scientific methods? Yes. The main methods of scientific thinking, including the foundation of science — the "reality checks" made by observing reality and using logic — are used by all scientists. But details change with time and culture, and vary from one area of science to another, and from one scientist to another.

Does historical science produce reliable conclusions? This is not a useful question, because it tends to generate a yes-or-no response claiming that "YES, [all] historical science [always] produces [totally] reliable conclusions" or "NO, [all] historical science [always] produces [totally] unreliable conclusions." Each of these extreme generalizations is wrong, because each implies the "all or none" claims inside the brackets, [ ].
If we want to avoid these wrong answers, we should avoid asking a general question that encourages simplistic "all or none" thinking. Instead, we should ask specific questions about particular historical situations and claims, to encourage sophisticated "degrees of reliability" thinking. We should carefully examine the evidence-and-logic for a particular situation, and try to determine the scientifically justifiable level of confidence in the reliability of a particular claim about that situation.

an application: In an effort to avoid false generalizations, in the sections below I claim only that a historical science can produce reliable conclusions [in some situations for some claims]. I defend this claim because I think it is true, but I won't defend a claim that seems false, a claim that every historical science will produce reliable conclusions [in every situation for every claim]. This page closes by looking at variations in the "justifiable level of confidence" for different situations and claims.

Operations Science and Historical Science

Yes, historical science can produce reliable conclusions.
Earlier, I say that scientific methods "vary from one area of science to another." Some variations in methods are due to differences between operations science (to study the current operation of nature, what is happening now) and historical science (to study the previous history of nature, what happened in the past). Both types of science are similar in most important ways, especially in their use of scientific logic, but there are minor differences. { Although some young-earth creationists try to contrast historical origins science with experimental empirical science (i.e., science based on observations), this is wrong because historical origins science IS empirical because it is based on observations. }
Although repeatable controlled experiments can be done in operations science, this is not possible for historical events. Sometimes, the limitations of historical data provide a reason for caution about conclusions. But this challenge has inspired scientists to develop methods that reduce the practical impact of data limitations, and historical sciences — in fields such as astronomy, radiometric physics, and geology — are authentically scientific.
In historical science, one way to "reduce the practical impact" is to use repeatable uncontrolled experiments to gather data. For example, other pages explain how observations of many Cepheid stars from many parts of the universe have shown that all Cepheids have similar properties, allowing them (and supernovas, which have their own consistencies) to be useful for measuring astronomical distances. These consistencies let scientists develop reliable descriptive theories, which can become explanatory theories that usually are related to (and are consistent with) explanatory theories in operations science.

Prediction & Retroduction, Mechanism & Agency
Because theory-based inferences are usually called predictions, the non-scientific meaning of "prediction" can lead to the mistaken impression that in science a logical inference must be made before an event occurs. But in historical science the timing of prediction is not a cause for concern, since a "prediction" (a logical inference based on a theory) can be logically valid even if it's made after an event has occurred, or after observations are known in a logical process of retroduction where the goal is to find a theory whose predictions will match known observations. In historical science, the goal is to describe and explain what did happen, not predict what will happen. In operations science a descriptive theory states that "what happened before will happen again." In historical science a descriptive theory might predict that "what happened in this situation also happened in other similar situations," or it might propose only that "this is what happened."
In some historical situations, only undirected natural process is involved, and a mechanistic explanatory theory can provide an adequate description and explanation. In other situations, "what happens" depends on the decisions and actions of an agent. This introduces an element of unpredictability, but a historical detective using scientific reasoning (in forensics, psychology, sociology, anthropology, archaeology, geology, astronomy, or history) only has to determine what did occur, not predict what will occur, in a descriptive theory. And in an agency explanatory theory, proposing that "agent action was involved" is the scientific conclusion of a historical detective.

Unobservable Causes of Observable Effects
Can scientists logically infer the existence of things they cannot observe? Yes, if an unobservable cause produces observable effects. This cause-and-effect principle is used in operations science. For example, even though electrons and ideas cannot be observed, modern theories propose electrons (in chemistry) and ideas (in psychology). Why? Because our observations are explained in the most satisfactory way by theories proposing the existence of unobservable causes (electrons and ideas) that produce the effects we observe.
Similarly, in historical science we can logically infer the existence of causes we did not observe, if these unobserved causes produced effects we can observe. Therefore, when skeptics ask "Were you there? Did you see it?", they are ignoring the principle that scientific logic depends mainly on observable effects, not observable causes. Because of this principle, even if an event or process was not directly observed, a plausible scientific theory can propose that the event or process did occur.

An Invitation to Examine the Evidence
Earlier in the page, I say: "Sometimes the limitations of historical data provide a reason for caution about conclusions." Sometimes, however, we have reasons to be confident about conclusions. Therefore, "we should carefully examine the evidence-and-logic for a particular situation, and try to determine the scientifically justifiable level of confidence in the reliability of a particular claim about that situation." When doing this we should also consider "the big picture" and the logical principle of multiple independent confirmations when the evidence-and-logic in a wide variety of situations leads to the same conclusion, and this occurs when we examine the abundant evidence for an old earth and old universe.
The radical relativists — the postmodern skeptics (and young-earth creationists) who challenge the reliability of science — claim that in historical science the evidence is always inadequate, so the conclusions of scientists must be determined by their nonscientific beliefs. Most scholars, including myself and other members of ASA, think these relativists are exaggerating the logical difficulties, making mountains out of molehills, and historical sciences have a solid foundation — the logical evaluation of empirical evidence — that provides a reliable way to learn about the history of nature and the fascinating world created by God. We encourage you to explore Origins Evidence where you can carefully examine a wide range of historical situations and claims, and you can decide which scientific conclusions deserve the highest level of confidence.

Historical Science is empirical and is scientific.

Scientific Methods in Historical Sciences

Operations Science and Historical Science

Historical Science
is empirical and
is scientific.