Good Science

The basic goal of good science is to develop a theory, paradigm, or model that provides a basis for research to understand the phenomena being studied. The model is useful only in so far as it helps to explain the observations. To this end, science develops by a formal procedure, usually termed "The Scientific Method."

Not all fields of science, however, arrive at conclusions in the same way. The physical sciences, such as physics and chemistry, use experimental forms of the scientific method: experiments are performed to gather numerical data from which relationships are derived and conclusions made. The more descriptive sciences, such as archaeology and anthropology, may use a form of the scientific method involving the gathering of information by visual observation of material remains and researching documentary evidence. What is common among all sciences, however, is the forming of a hypothesis to explain observations that are made, the gathering of data, and, based upon this data, the drawing of conclusions that confirm or deny the original hypothesis. The difference between the types of sciences is in what is considered data, and how data is gathered and processed.

The basic steps involved in the scientific method, especially as applied to archaeology, are as follows (the order of these steps is not rigid):

Make observations (collect facts and data). All science must begin with observation. Science is only concerned with objects or events that are observable, either directly or indirectly. An example of indirect observation is the study of atoms which are not readily observed, but their effects are observed using instruments.

In archaeology, objects or events are usually observed in the natural world, or it may be that previously collected data is examined, in which case primary rather than secondary sources should be used. It is important that the observations be repeatable and verifiable.
Create a hypothesis to explain the observations. A hypothesis is a tentative explanation to account for the observations made. The hypothesis unifies the data into a generalization from which predictions can be made. Truly scientific hypotheses must be testable; thus are erroneous hypotheses able to be falsified.

The step from isolated observations to generalization is often called induction, or inductive reasoning. The step from generalized question to prediction of outcome is often called deduction, or deductive reasoning.
Deduce the implications of the hypothesis. Implications are predicted based on the hypothesis. The hypothesis might be thought of as the first part of an "if ... then" statement; the "then" predicting the result of the hypothesis. It is these implications that are then verified or rejected by testing through further observation.
Test the implications. Further observation and experimentation is made to collect data, which are compared with the predicted implications to determine if the data confirm or deny the hypothesis. It is very important that all data be considered, not just those that support the hypothesis. Also bear in mind that even if the data support the hypothesis, the hypothesis is not necessarily proven to be true. It simply renders the premise that much more plausible. The ultimate test of the validity of a scientific hypothesis is its consistency with the totality of other aspects of the scientific framework.
Re-evaluate the hypothesis. Was the hypothesis confirmed or denied by the further observation or experimentation? If it was denied, then a new hypothesis must be formed to encompass the new data (back to step 2 above). A hypothesis is valid only so far as it is consistent with the data accumulated. A good hypothesis is also consistent with the greater corpus of scientific knowledge; if it is not then it is incumbent upon the one proposing the hypothesis to reconcile the contradictions before it can be considered to be true. If the evidence in favor of a particular hypothesis is convincing, then the hypothesis is elevated to a theory A theory is a formalized set of concepts that organizes observations and predicts and explains phenomena. A theory is the fruit of much research and it demands a solid empirical base of evidence.
Subject the hypothesis to peer review. A valid hypothesis will withstand outside scrutiny by other researchers in the field. Making the hypothesis available for constructive criticism is a necessary step in the formulation of valid theories. It allows others to repeat steps 3 and 4 above, thus providing a wider base of knowledge to verify the hypothesis. If any criticism cannot be effectively refuted, then the hypothesis must then be reformed (again, back to step 2 above). Scientists, like other human beings, may individually be swayed by some prevailing worldview to favor certain results over others, or to "intuit" some broad theory that they then seek to prove. The scientific community as a whole, however, judges the work of its members by the objectivity and rigor with which that work has been conducted; in this way the scientific method prevails.

The scientific method is a process by which we systematically advance our understanding of the world. True scientists adhere strictly to this method. It is considered to be the foundation of all branches of science; in fact, a result can only be called 'scientific' if it has been subjected to the standards of the scientific method. Both the power and the limitations of science are the result of the rigorous attention to this method.

In The Demon-Haunted World (p. 261), Carl Sagan wrote:

Science is different from many another human enterprise -- not, of course, in its practitioners being influenced by the culture they grew up in, nor in sometimes being right and sometimes wrong (which are common to every human activity), but in its passion for framing testable hypotheses, in its search for definitive experiments that confirm or deny ideas, in the vigor of its substantive debate, and in its willingness to abandon ideas that have been found wanting. If we were not aware of our own limitations, though, if we were not seeking further data, if we were unwilling to perform controlled experiments, if we did not respect the evidence, we would have very little leverage in our quest for the truth. Through opportunism and timidity we might then be buffeted by every ideological breeze, with nothing of lasting value to hang onto.