Is it Appropriate to Include Personal Correspondence in the Appendix of a Thesis?

Question

While conducting research for my dissertation, my collaborator and I discovered a mathematical error in published work and this error was confirmed by the author through personal correspondence. On the surface, it appears as a minor error, however it effects certain mathematical statements. The author of the work unfortunately has not published the correction in the errata for the work. It has been over a year now since our last correspondence.

The area of research I'm conducting is not widely studied so there isn't a large community of academics who are familiar with subject matter so this is unlikely to be something that will be checked by the wider community.

In the manuscript, I have written that we discovered an error and corrected it and that the correction was also confirmed by the author, and the only proof I have is email correspondence from the author. After I graduate, my email account will be shut down after a year. Therefore, would it be alright to include the correspondence I have as an appendix in the thesis in order to verify the statement I made about discovering the error and having our correction verified? The language in the email is formal and professional.

Answer 1

You can only publish email correspondence in your thesis if all people involved in the email communication agree. Anything else is highly unprofessional and also unethical.

On the other hand, if you have clearly demonstrated that the manuscript had an error, there is no need to add those email. You could write that this has been confirmed by the author and cite a "private communication".

Regarding the emails, there should be no problem to save the emails even if your account is deleted.

Answer 2

In some cases you can also write:

The mistake described above has been confirmed [15] by the authors of [12].

where the extra citation may read something like:

[15] Shot, Big and Fry, Small. Personal communication, September 9th, 2020.

Answer 3

A mathematical argument speaks for itself and its validity does not hinge on the blessing or confirmation of a single individual, even if the argument corrects a mistake that individual has made previously. So I think your premise that you need to include anything about the error being confirmed by the original author as some kind of “supporting evidence” is simply false. The fact that the author confirmed what your said is something that can be mentioned if you’re doing it as a way to save the author a bit of embarrassment, but is otherwise irrelevant. If you simply provide an explanation of the error and the details of how it is corrected, that will completely suffice to convince any readers of the validity of what you are saying. No emails need to be quoted.

As for your literal question: no, as a general rule it’s a terrible idea and quite inappropriate to quote a personal email in a thesis or other publication without explicit approval from the author of the email. But as I said that’s sort of the wrong question to ask for your particular situation.