The author claims that Van Eyck notices details we'd otherwise miss out and uses the Arnolfini portrait as supporting evidence. However it's possible that artifacts such as the beads appear not because he saw the world differently, but due to his artistic choice of tools. He may have used an optical projection device, a "perspective machine" -- Which means that his process may not have allowed for skipping the inclusion of the beads.
See:
- https://theconversation.com/the-mysterious-optical-device-ja...
- https://hal.univ-lorraine.fr/hal-03287031/file/VanEyckPerspe...
- https://link.springer.com/chapter/10.1007/978-3-319-31903-2_...