- Describing scientific knowledge as a set of abstract theoretical statements, Reynolds, in chapter 5, identifies three types of conceptions arrangement representing a theory as: “set-of-laws”, “axiomatic” and “causal process”. A set- of- law theory is consisted of a number of laws, all being supported by empirical research, and have some ‘operational definitions’ making them able to be measured directly. An axiomatic theory is a set of interrelated collection of definitions and statements, in the form of axioms and propositions (derived from axioms). A causal process theory is defined as a set of definitions and (existence and causal) statements being interrelated to each other, and unlike the axiomatic theory in which statements are categorized into axioms and propositions, all statements used in this kind of theory are equally important.

- In comparison of these three forms of Theory conceptions, Reynolds refers to some advantages and disadvantages of each one. For set-of-law theories: lack of any “sense of understanding” , prohibition of using un-measurable concepts and hypothetical constructs in statements, and large size of set-of-law theories versus the point that  more than %90 of human knowledge match these kind of statements; for axiomatic theories: difficult selection of axioms, failing to provide a sense of understanding, versus the ability of hypothetical concepts, smaller size, and efficiency of research; and for causal process form: difficult decision on whether all required steps and statements have been specified, versus being used, in a high rate, by social sciences.

- In chapter 6, Reynolds talks about testing of a theory. One important thing he mentions, is that one reason that it seems impossible to prove the truth of an abstract statement, is that it could be proved to be false, in the future. Then, he refers to the extent of correspondence between a statement and the results gained by empirical research, as the most important criterion of evaluation of that statement. In other words, he says that in this way, concrete statements support the usefulness of an abstract statement.

-Statistical decision procedures can be used in order to prove the truth or falsity of a statement. Statistics can be classified into two types: “descriptive statistics” and “inferential statistics”. The first type is used for description of features of an event or phenomenon. The second one is a procedure for supporting decision making of individuals about recognizing a description of a phenomenon as to be true.

- In chapter 7, the author discusses about different strategies used for developing a scientific body of knowledge. He introduces two strategies: ‘research-then-theory’, and ‘theory-then-research’. In the first one, one assumes that there are some real patterns in the world and scientists should discover them, like the approach of Margaret in the cartoon. The second, theory-then-research strategy, assumes that scientists impose some descriptions on phenomena that they study. Then he analyzes strengths and weaknesses of each of these two strategies.

- Then, Reynolds identifies three types of research methods related to social science: ‘individual observation’, ‘survey’, and ‘experimental’. In the first type, researcher observes a social science phenomenon, directly. In the second one, a group of people or social systems are measured concerning specific individual attribute. In the last one, experimental, in a controlled manner, the phenomenon is reproduced and the different measurements are made.

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-My viewpoint about the best strategy for developing a scientific body of knowledge is that a convenient combination of the two strategies of research-then-theory and theory-then-research would be the best. Because, hardly a scientist can discover all laws at the time he/she begins his/her investigation and thinking about a phenomenon, and also it is difficult to define all the variables needed for being measured for a phenomenon. So, considering a rough answer until one can reach to an exact and final answer would be the best solution.