Studies in the Methodology of Natural and Social Sciences explore from the point of view of philosophy, philosophy of science, methodology and semantics the methods of pretheoretical (empirical) measurement, theory construction, and methods of measurement that are already based on scientific theories. This exploration targets both the natural and the social sciences. In the field of natural sciences, subject to theoretical and metatheoretical analyses are Huygens' experimental and computational methods for determining the acceleration of gravity, the methods of constructing a thermometer, and Newtonian mechanics. With respect to the field of social science, it analyzes Marx's methods of theory construction presented in his work in the area of economics, the methodological approaches employed in David Ricardo's theory of value, sociological Grounded Theory, Rational Choice Theory, and Historical Sociology. A significant attention is given to the philosophical reconstruction of the categories employed in the measurement methods and in the methods of construction of the analyzed theories.