A pdf file of this paper is available. Also, an html file is now available.
In this very personal paper, the author gives his perspective on the development of set theory and model theory, and discusses some of his main sources of motivation. What would one want to read in an article like this? On p.9 of the article the author gives his answer to this question: "A reasonable guideline may be this: what would I like to be able to read by a reasonable mathematician of Cantor's time? A possible answer: why he has dealt with particular problems, what his views were, and something about himself and his colleagues."
The article ends with the following very quotable thesis: "Never let ideology or `good taste' stop you from proving a good theorem."