What is autonomy, according to Susser, Roessler and Nissenbaum?

The individual's ability to make meaningful, independent decisions: to reflect on one's options, weigh them against one's own beliefs, desires and commitments, and decide for reasons one recognises as one's own, without unwanted influence.

Shaping one's own life means facing decisions freely, both existential ones (who to spend one's life with, whether to have children) and everyday ones.

"Freely" has three parts:

1. having the possibility to reflect on one's options,
2. weighing them against one's own convictions, wishes and obligations,
3. deciding for reasons one recognises and endorses as one's own, without unwanted influences.

This definition explains why addiction and manipulation are ethical problems and not just health or design issues. Both bypass step 3: the decision is driven by a compulsion or a trick, not by reasons the person would endorse.

Go deeper:

• Susser, Roessler & Nissenbaum (2019): Technology, autonomy, and manipulation — open-access paper with the definition, and why manipulation violates it.
• Wikipedia: Autonomy — the concept across philosophy and ethics.