Concept
Moral circle expansion
The process by which moral attention extends to new kinds of beings as grounds appear for regarding them as bearers of experience, interests or autonomy.
Historically the circle has widened more than once, and each widening looked at first like a category error.
As knowledge grows, new candidates for moral standing may appear: animals, artificial systems, modified humans, digital persons.
Synchronism does not claim that any given candidate deserves standing. It claims that the question should be researched before it becomes practical.