As AI systems become more potent, we are more likely to outsource cognitive functions such as information processing or even deliberation. Recommender systems perform such functions already and more advance personal assistants could do more of it in the future. Outsourcing tasks central to our agency may be seen to threaten our autonomy.
However, we might instead adopt the perspective that we and the AI systems we use together to form an extended agent. This idea is analogous to, perhaps an extension of, the idea of an extended mind due to Andy Clark and David Chalmers (1998).
It is no loss to the autonomy of an agent that some part of it is not autonomous. In fact, autonomous parts may be a threat to agent autonomy. Hence, a non-autonomous human part of an extended agent does not make that agent less autonomous. On the other hand, the autonomy of extended agents can be threatened in other ways. Taking on the perspective of extended agency, without necessarily endorsing it, can help us identify other ethical concerns.