How can I infer psychological intentions from email corpus using text mining?
DISCLAIMER : I'm not sure that this will be the answer you are looking for but I'll give a try.

According to Noam Chomsky


  Language is a process of free creation; its laws and principles are
  fixed, but the manner in which the principles of generation are used
  is free and infinitely varied. Even the interpretation and use of
  words involves a process of free creation.


On one hand, data or text mining the combined large lexical data resources of linguistics and psychology suggests that the linguistic variable of 'word frequency' should be rehabilitated in psychology.

But you have to remember that, correlation does not imply causation.

This said, there is not much way to apply cross text mining with psychological intuition. In other words, use cases are not too many.

You can always try quantitative text analysis. It is a set of techniques stemming from the social sciences where either a human judge or a computer extracts semantic or grammatical relationships between words in order to find out the meaning or stylistic patterns of, usually, a casual personal text for the purpose of psychological profiling etc. 

And by psychological profiling, I'm talking about offender profiling per example. 

You can get more information upon that on the following websites :


Criminal Investigative Research &amp; Analysis
http://www.psychlotron.org.uk/ article  about criminal profiling.
Here is a very intersting article about criminal profiling for beginners.


You can also try to take a look at this presentation by Harold Baize who talks about the intersection of text mining in the content analysis of psychology.

I hope this can help!