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Legal Argument

Overview

Module description

This module provides a grounding in analysing, interpreting and developing arguments. We will focus on the basics of logic (deductive and inductive inferences and their associated fallacies) and their application in legal argument. We also introduce the basics of rhetoric (the art of constructing persuasive argumentation), equipping you to communicate persuasively.

These skills are essential for you to be able to understand, critically evaluate and respond to claims and arguments with which you are presented in legal and other contexts. They are also essential for you to be able to develop your own arguments.

Indicative syllabus

  • Logical basics; deductive inference; categorial and propositional logic; modus ponens and modus tollens; validity v soundness; logical transposition; deontic logic
  • Formal fallacies; deceptive appearance of invalid inferences; denying the consequent, affirming the antecedent, undistributed middle; connection to fallacies of ambiguity
  • Inductive arguments; empirical and rational explanation; argument by analogy; conductive arguments (to the best explanation); universals and particulars
  • Informal fallacies; false cause, false analogy, equivocation, begging the question, straw man, etc
  • Logic and legal reasoning; interpreting the ratio of prior decisions, extrapolating from a previous line of cases; argument by analogy; interpretation as conductive argument, ratio as deontic argument
  • Aristotle’s modes of persuasion; ethos, logos, pathos; connection to the emotions
  • Cicero’s canons of rhetoric; the art of arrangement and delivery
  • Entwinement of logic and rhetoric in legal arguments; distinguishing logical from rhetorical points; overlap of rhetoric and logic; Rivonia trial

Learning objectives

By the end of this module, you will be able to:

  • distinguish between valid and invalid inferences in propositional and categorial logic
  • identify formal fallacies in arguments
  • distinguish between valid and sound arguments
  • evaluate the strength of inductive arguments
  • identify informal fallacies in arguments
  • distinguish between the strength and the cogency of inductive arguments
  • distinguish between the persuasiveness and the rational force (validity, soundness; strength, cogency) of real-life arguments
  • apply these abilities to the analysis of legal arguments in decided cases and submissions
  • demonstrate the application of these abilities in spontaneous written and oral communication
  • construct arguments of your own that exemplify logical and rhetorical qualities, in spontaneous written and oral communication, particularly in legal contexts.