I’m interested in what you say about Lotus Improv, but I’m having trouble understanding what it has to do with Ragic Builder.

  He's old enough that he should know better.

Who is old enough, the Ragic Builder creator or PG? That person should know better than to what?

The author Alan B. Downey has released quite a few free books:

Check out http://www.greenteapress.com/ including:

Think Python : http://www.greenteapress.com/thinkpython/thinkpython.html

Think Bayes : http://www.greenteapress.com/thinkbayes/index.html

Think Complexity : http://www.greenteapress.com/complexity/index.html

Think Stats : http://www.greenteapress.com/thinkstats/index.html