This book is written for anyone involved or interested in learning ordinary language reasoning. It provides an introduction to methods of critical and creative thinking, including the construction of arguments as they appear in ordinary discourse, and the reconstruction and evaluation of such arguments. Although this book is not primarily an introduction to methods in formal logic, we do provide an introduction to categorical and propositional logic. Throughout, we emphasise techniques for producing arrow diagrams of arguments in ordinary language in order to understand and clarify their structure in order to then assess whether they represent good reasoning. If you work your way carefully through this book, you will become better at reasoning both in terms of understanding and clarifying other peoples arguments and also at producing increasingly sophisticated and compelling arguments of your own. You will learn how to recognise common but often seductive mistakes in reasoning and so be empowered to avoid making these mistakes yourself. With perseverance, your writing skills will improve. Your oral presentation skills will improve and you will hone your ability to define crucial terms in argument, debate, and discussion. Ultimately, you will learn how to ‘think outside the box’.

This book has been written in the belief that it is possible for critical and creative thinking to be a thoroughly exciting and practical enterprise, highly enjoyable, and motivating an ongoing appreciation of reasoning and arguing about things that matter to you and others. We have deliberately tried to engage our readers throughout, when appropriate in a lighthearted spirit.

In Chapter 1, ‘Basic Concepts of Reasoning’, we introduce the key concepts of argument and reasoning. These include the principle of charity, deduction, validity and soundness, and induction, strength, reliability, and cogency.

In Chapter 2, ‘Diagramming Reasoning’, we introduce a method of diagramming arguments. This is especially useful for clarifying the structure of arguments in keeping with the idea that we need to understand carefully an argument before we begin the task of evaluation.

In Chapter 3, ‘Evaluating Arguments’, we provide heuristics for assessing the strength of inferences, both deductive and inductive, as well as the truth or falsehood of reasons and conclusions.

In Chapter 4, ‘Diagramming: Reasons For and Against’, we extend the method of arrow diagramming to diagram objections to arguments and show how this can be used to evaluate such objections.

In Chapter 5, ‘Forms of Argument’, we present and discuss common forms of deductive and inductive arguments.

In Chapter 6, ‘Reconstructing and Constructing Arguments and Writing Evaluative Essays’, we show how all of the previous chapters inform our capacity to accurately represent and interpret the arguments of others as well as developing our skills in building our own arguments. We then apply this to yield guidance in writing an argumentative essay.

In Chapter 7, ‘Fallacies’, we discuss many of the most common mistakes in reasoning.

In Chapter 8, ‘Categorical Logic’, we deal with the elements of the logic of arguments about categories or kinds of things, both from a Boolean and an Aristotelian perspective.

In Chapter 9, ‘Propositional Logic’, we deal with the elements of the logic of arguments about statements or propositions. We show how to translate claims into the language of propositional logic and show how to test statements for consistency, how to classify them, and how to use the direct and indirect truth-table methods to ascertain the validity of deductive arguments in propositional logic.

In Chapter 10, ‘Definitions’, we explain the importance of a good definition, discuss what counts as a good definition, and show how to produce one.

In Chapter 11, ‘Practical Applications’, we draw out the implications of our entire discussion of ordinary language reasoning in order to learn how to ask good questions and how to think about moral, legal, scientific and business reasoning.