Optical illusion triggers debate about hidden number inside circle

This optical illusion has gone viral once again because it has left netizens divided over a number it hides at the centre., Viral News, Times Now

Optical illusion reveals a hidden number that everyone is seeing differently

Can you spot the hidden number in this optical illusion? Only 1% can find it within 20 seconds

Optical Illusion: Search For The Hidden Circle In This Gird Of Squares

Experimental demonstration of separating the wave‒particle duality of a single photon with the quantum Cheshire cat

Can You Spot The 16 Hidden Circles In This Optical Illusion?

What are some great optical illusions? - Quora

Photos of Mind-Boggling Optical Illusions and How They Work

Can you spot all the hidden circles in this optical illusion

Belief of agency changes dynamics in sensorimotor networks