In his Addams family laboratory, Uncle Fester has finally figured out how Thing is animated given that it is not attached to a human body.
The secret is mycelium - the fungal network attached to the roots of mushrooms. Fester found the mycelium clustered around Things finger nails and it is this fungus that is responding to changes in light or heat, animating the handy hand so beloved by Morticia.
This does not explain how thing can deliver the mail or play chess but Fester admits his work is only in the early stages.
Wednesday Addams told FNN:
You severely underestimate my apathy to this news.