I can't see them all at once, can you?
There are 12.
See the science here:
Ninio, J. and Stevens, K. A. (2000) Variations on the Hermann grid: an extinction illusion. Perception, 29, 1209-1217.
Dr. Yan L. Liang, OD
Markham Optometrist
www.wardenoptometry.ca
Contact Warden Optometry to book your appointment today.