A System of Logic Ratiocinative and Inductive: Being a Connected View of the Principles of Evidence and the Methods of Scientific Investigation

Abstract

The advancement of scientific knowledge requires not only inductive logic but also subsidiary mental operations such as precise observation, the standardization of descriptive terminology, and the rigorous formation of general conceptions. These operations ensure that language serves as an accurate instrument for thought, facilitating the categorization of natural kinds and providing the requisite materials for inductive inference. Systematic errors in the reasoning process are categorized into five distinct classes—prejudices a priori, and fallacies of observation, generalization, ratiocination, and confusion—to establish a framework for the objective evaluation of evidence. Applying these logical principles to the “moral sciences” requires a shift from purely experimental or purely abstract methodologies toward a concrete deductive method. Under this framework, the laws of individual human nature, established by psychology, provide the foundation for ethology—the science of character formation—and sociology. Because social phenomena are governed by a complex consensus of interacting variables, they must be investigated through the inverse deductive or historical method, which verifies empirical generalizations by connecting them to the ultimate laws of mind. This scientific structure further differentiates the logic of theory from the logic of practice, where teleology defines the ends of conduct according to the principle of general utility. – AI-generated abstract.