Is it plagiarism if a robot created it?

I’m in the process of grading the final exam I give for my class.  Included in the exam is a question I wrote that was meant to demonstrate their understanding of plagiarism.  Here is the question:

Suppose 30 years from now you receive a paper from one of your students of such quality you suspect they didn’t actually write it.  When confronted, they admit that they had their robot “Curtis” write it for them.  They argue that since it wasn’t another person who wrote it for them, it’s not plagiarism.  Do you accept their paper?  Justify your answer.

As I’m grading, I was noticing a disturbing tendency to agree with the student.  Finally, one of my students’ answered in a way that really demonstrated what their thinking was, and it came down to the way they defined plagiarism.  If they defined it as ‘taking work not your own and claiming that you created it’ they denied the paper.  If they defined plagiarism as ‘taking another person’s work and claiming it as your own’ then they would agree that the student was correct that it’s not plagiarism, but wouldn’t accept the paper.

So in the end, it really hedged on the presence of “person” in the definition.  They don’t imagine robots fitting the description of ‘person’ so it wouldn’t be plagiarism, as long as their definition of plagiarism included the word ‘person’ in it.  I just find that incredibly interesting.