Christopher Register (2025), Philosophers’ Imprint 25: 47, 1–14 — DOI-10.3998/phimp.7576
Key takeaways
- The body has a dimension of “depth” (how abstract or high-level its parts are) as well as spatial breadth. Register argues that body parts are fairly high-level objects, and bodily rights and interests concern only events that are not “high-level neutral”. So a person’s BCI software can be a body part while the cloud server implementing it is not.
Seeded from the abstract and a skim, before the reading in NOTE-151. What follows is what the work says about itself.
A body extends through space, so it has breadth. It also has depth: roughly, the level of abstraction of its parts. For moral purposes the body is characteristically fairly high-level, so individual molecules are not really within the “moral body”, the body that figures in bodily rights and interests. Register develops this notion and uses it to resolve puzzles about brain–computer interfaces, some of whose computation runs on external or cloud hardware owned by third parties.
Standing in the record
Filed from the 2026-09-26 sweep of the papers-feed tracker for philosophy: 10 seconds of active reading over 1 session. It was filed Deferred, unread. NOTE-151 is the close reading of 2026-09-26, and it placed the work: Active — worth reading as a short, clearly argued proposal that separates a moral “body-part” relation from ordinary parthood by level of abstraction, and applies it to cloud-hosted BCIs. It is an argument from cases with the key ontological step hedged, not a worked-out mereology.
When seeded, before the reading in NOTE-151, the entry gave a priority for a deeper reading: low — t=10 s. The skim captures the proposal and its application well.
What the seeding asked a deeper reading to check (NOTE-151 is that reading):
- The software-vs-hardware “depth” distinction transfers directly to questions about where an AI system, or a user’s extended cognitive tool, is located. It pairs with LIT-097 (extended mind) and LIT-147 (BCIs and mental causation), and with Birch’s LIT-111 point that conversations are spread across data centres.
- Check §4, which argues that existing theories of the body already support depth. It was not read in detail, and the ontological backing (real definitions à la Fine and Rosen) carries weight.
- The context-sensitive threshold for “high-level” may make the principles hard to apply. A deeper reading should test them on the brain-tissue case the paper itself flags.
Access when seeded: The journal site first returned an Anubis bot challenge to a browser user agent. A plain curl user agent then got the full open-access HTML article (CC BY-NC-ND 4.0). Read the abstract, keywords, the “How to cite” block, §1 Introduction, §2.1–2.2, §3 Defining Depth, §5 Two moral principles, §6 Depth and BCIs and §7 Conclusion. §4 was read by heading only. “Published on 2025-12-12” per the article page and Crossref; OpenAlex gives 2025-08-21, possibly an earlier online-first date, unverified.