Philosophy of Logic Part II

Philosophy of Logic Part II

Just as pertinent knowledge and expertise are required when making right decisions and choices, certain skills and rules are necessary when attempting to reason correctly. Equipping one with logical skills and rules is the major aim of logic or philosophy of logic. This comprehensible course on logic is divided into two parts: the first part (sections I and II) give an overview of logic and common informal fallacies.

Course code: FIXEN023

Professor: Isaac Mutelo


Clearly, epistemology concerns the meaning and nature of truth, whether human beings really know what they claim to know (or think they know) and how knowledge and its attainment can be made more reliable.

Sections of the course 

The third section focus on formal logic. Since formal logic has become broad today, the focus will be on categorical syllogism which employs deductive reasoning. Categorical syllogisms are the most common and widely studied in formal logic. Logicians recognises Aristotle as the earliest to have developed the first system of formal logic and raised several essential problems in the philosophy of logic. The third section begins by attempting to define a syllogism, and then proceeds to discuss the structure of a categorical syllogism. Having done so, the section critically discusses the different between good arguments (valid) and bad arguments (invalid). Therefore, the aim of the third section is to introduce one to what syllogisms are, their structure, core elements and how one can determine their validity or invalidity by means of counterexamples, analysis or mere intuition.

The fourth section continues the discussion on categorical syllogisms. The section begins by exploring the basic forms of categorical propositions as well as syllogistic moods and figures. Having discussed moods and figures, the discussion will progress to how one can determine the validity of different moods belonging to the four different figures. The fourth section also highlights six rules of syllogisms and the formal fallacies that are involved in cases where the rules are violated. By examining whether the rules of syllogisms are violated and the related formal fallacies, one can determine the validity of a standard-form syllogism thereby developing cogent and logically valid arguments. The final part of the fourth section will discuss the Venn technique of testing for the validity of categorical syllogisms. Although the simplest ways of verifying the validity of a syllogism consists in figuring out its mood and through counterexample, the Venn diagram technique is considered as the formal way of testing the validity in logic.