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Know of a resource missing from this page? Let us know... 

This page lists textbooks (or textbook-like-things) which are freely available online.  Of course there are zillions of other regular textbooks, many of which have an online presence (mainly just promotional pages). 

Research Methods Knowledge Base by William M. Trochim, Cornell University
First class online resource.  This is essentially a textbook in one form of advanced critical thinking. "The Research Methods Knowledge Base is a comprehensive web-based textbook that addresses all of the topics in a typical introductory undergraduate or graduate course in social research methods.  It covers the entire research process including: formulating research questions; sampling (probability and nonprobability); measurement (surveys, scaling, qualitative, unobtrusive); research design (experimental and quasi-experimental); data analysis; and, writing the research paper.  It also addresses the major theoretical and philosophical underpinnings of research including: the idea of validity in research; reliability of measures; and ethics."

Psychology of Intelligence Analysis, by Richards J. Heuer, Center for the Study of Intelligence, Central Intelligence Agency
A useful guide to critical thinking in the light of insights from cognitive psychology about how human thinking goes wrong. Despite the title, the book has little essential connection to intelligence analysis; it is really just about thinking in general. 

Introduction to Probability by Charles M. Grinstead & J. Laurie Snell
An entire, 500+ page textbook on probability.  Designed for use in a one-semester college course.  Not the best "self-help" guide for novices, but could be a very useful resource for those who already have some familiarity with probability and are comfortable with a moderately technical treatment. [20 Oct 03]

Decision by Objectives by Forman and Selly (pdf file, 2.46mb)
Complete textbook on decision making.  Aimed at management, but the contains a lot for the general reader (or decider?).  Centered on a general decision framework known as the Analytic Hierarch Process (AHP).  This may not be the best textbook on decision making out there, but there is plenty of value here, and it does have the advantage of being freely downloadable. [7 June 04]

Introduction to Logic: Evaluating Arguments by Ed Teall
"Ed Teall’s Introduction to Logic focuses on building skills to critically evaluate arguments, as well as how logic is applicable to everyday situations. Animated and interactive drawings demonstrate the completion of Venn diagrams, truth tables, and deductions. In addition, interactive multimedia, including digital interactive video, demonstrates important topics."
This textbook is available for purchase online; instructors can peruse it for free. It has too much traditional logic content to be a good critical thinking textbook, but still, there is plenty of good stuff in it, and the interactive animations are worth checking out.

Argument Analysis, by Ed Brandon
"This little book is intended to help people deal with arguments. In particular, it is intended to help people see more clearly what is going on when a person gives reasons for believing something or doing something, and to see some of the pitfalls in the way of clear reasoning..."

Steve's Primer of Practical Persuasion and Influence by Steve Booth-Butterfield
An online textbook on persuasion, influence and attitude.  Developed for use in a university course.  Very "bare bones" (no pictures) but written in a very accessible, colloquial style.  [21 July 03]

Last updated: 22 Jun 2007