My middle name is actually Thomas. I chose to use “M Thomas” as a pen name out of respect for my father, who taught me how to write. As a professional communications writer, he was responsible for lots of public documents for the NYS DMV, including traffic safety reports, driver manuals, press releases from the Governor, all sorts of “my boss will feel the need to edit this, so I will deliberately leave behind something for him to do so as he doesn’t screw up the entire thing” document.
I may or may not have adopted this strategy in my own professional work (I certainly adopted the attitude…)
Another reason is because I had a baby brother named Thomas. He passed away before reaching five months old when I was not quite 11. It had a major impact on me as a child (and indeed as the adult and as the father I am).
I have no sons. It bothers me that I may be the last Thomas in our family. For a while, anyway.