For over 2,000 years, a course in logic has been considered an essential component of a university education. And for good reason: The study of logic will sharpen your intellect and expand your thinking. This website accompanies and supplements the standard logic class taught at most colleges and universities.

What is Logic?

Logic is the study of the principles of correct reasoning. The principles of logic are universal guides to correct reasoning, just as the rules of arithmetic are universal guides to correctly adding, subtracting, multiplying, and dividing numbers. You can improve your reasoning by studying the principles of logic, just as you can improve your number-crunching abilities by studying the principles of mathematics. Because correct reasoning can be applied to any subject matter whatsoever, the number of potential applications of logical theory is practically unlimited. 

Read More at: Philosophy News | What is Logic? By Paul Herrick


The videos, slides, lectures, and quizzes on this website are keyed to Introduction to Logic by Paul Herrick (Oxford University Press, 2012).

  • Short Videos on Logical Theory

    One hundred lessons to help lock in the basic concepts of modern logic

  • Let’s Get Logical

    The Many Worlds of Logic recommends the “Let’s Get Logical” YouTube channel for more instructive videos on the basic principles of modern logic. These interesting lessons are produced by Timothy Linehan, Professor of Philosophy at College of the Sequoias in California and they reference and are keyed to the text Introduction to Logic by Paul Herrick.

  • Slides

    Step by step demonstrations on topics ranging from introductory logic to modal proofs

  • Short Quizzes with Answers

    Exercises to test your understanding

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