At the opening of this short series of lectures, I briefly presented five issues which fall under the heading of “economics and language.” By now you have realized that the issues were indeed quite distinct. I found it difficult to point out the common factor among the topics other than the title and the speaker.

I am deeply grateful to three people who have (surprisingly) agreed to comment on this manuscript. Tilman Börgers, who was also the original discussant in Cambridge in 1996, Bart Lipman, and Johan van Benthem. Tilman and Bart bring some perspectives from economists, and Johan brings his perspective as a logician. It must be hard to write such a review, especially when one wants to criticize the author. Thus, I wish that the reader will pull out from the comments especially the critical comments and the suggestions for further research.

The three discussants helped me out in finding the common features of the first four essays. As Bart Lipman puts it, the first four chapters touch three related questions: “What gives a statement its meaning?,” “Why is language the way it is?,” and “How does language affect action?”

The discussants also persuaded me that the last chapter is very different in nature. If it belongs to this book beyond my rhetorical use of the phrase “economics and language”, it is only because it presents my general approach to economic theory, which is a thread running through these lectures.