Click button to enter the Power of Logic tutorial.
The Power of Logic Tutorial
The Power of Logic is a web tutorial for C. Stephen Layman's introductory textbook, The Power of Logic. There is nothing to download. The entire tutorial runs online. The tutorial is meant to assist students and teachers who are using Layman's textbook. Most of the exercises in the text can be done interactively via this on line program. If a student makes a mistake, the program provides an error message. Often there is helpful feedback about the mistake along with the opportunity to repeat the problem.
The Power of Logic is regularly updated with more exercises and improved user interfaces. The administrators of this web site welcome comments and bug reports.
In general, The Power of Logic is easy to navigate and use. A column on the left of the screen handles navigation. (A permanent link to the main menu of textbook chapters would be a helpful addition.) The user should spend a few minutes reading the General Help page as well as skim the special help pages on Venn Diagrams, Truth-Tables, and Proofs. The user really begins to use the program by clicking on the textbook chapter, section and exercise set which she wants to do. As long as the user is alert to messages on the screen, the program is easy to use. About half of the exercises can be accomplished with mouse clicks. The rest require some typing. Although the exercises are taken out of the Layman text, students using another introductory textbook should be able to use much of this tutorial. For example, the exercises on basic concepts, categorical logic, and statement logic are similar to the exercises in the Hurley text.Chapter Five, Section One of the Layman text covers symbolization of ordinary language sentences into the four standard forms of categorical propositions. Most of the exercises on categorical logic assume facility in translating ordinary language sentences into standard form. This section is fundamental for doing the exercises in Chapters Five and Six. Venn diagrams are easy to construct. Everything is done quickly with mouse clicks on the diagram and on radio buttons. One can effortlessly add or remove shading or Xs anywhere in the diagram. If the diagram is not done correctly, the program offers helpful feedback and the opportunity to revise the diagram.
The material on translating ordinary language sentences into statement logic is virtually the same as any introductory logic textbook. The computer program accepts unusual, but correct translations into sentence logic. Unfortunately, it takes more time to construct truth-tables with The Power of Logic than it would to construct the tables with pen and paper. One should be able to build an 8 row column in two to three seconds. With The Power of Logic one has to enter a capital T or F, cursor down, and then use the space key to line up the column properly. This must be repeated for each truth-value. Fortunately, the program does the reference columns automatically. To its credit, The Power of Logic truth-tables are easy to construct once one gets the hang of it. Furthermore, it catches errors and offers feedback.The material on proofs for statement logic uses a standard set of natural deduction rules. The computer program is an excellent tutorial aid for learning the rules and learning how they are applied. The sections on annotation of proofs and recognition of correct versus incorrect employment of rules are both user friendly and effective. Actual proof construction on the proof checker is tedious. It is easy to learn how to use the proof checker. However, the user has to type every statement and every justification working top down. The proof checker is just a proof checker. If a student has any doubts about the proof she constructed with pen and paper, she can run it through The Power of Logic proof checker to find out whether or not it is correct. As long as the proof checker takes this limited role, it performs very well.
This is a summary of some of the interactive exercises included in The Power of Logic. Look at the Table of Contents yourself. Pick a chapter that interests you. Then choose a section and one of its exercise sets. You can always back out and select another set. You can spend countless hours on this interactive web site. (I did.) It is almost as much fun as a computer game, and a lot more rewarding.