In the present state of our knowledge, it would be useless to attempt to speculate on the remote cause of the electrical energy... its relation to chemical affinity is, however, sufficiently evident. May it not be identical with it, and an essential property of matter?
I don't know if it's harder but when you're playing a real person you want to honor their memory - even if they're a criminal or someone that the public loathed. That can be challenging.