We’ve heard there are supposed to be 7 horses (including some partial horses, like a horse head and rear) shown in the picture. If you do not see seven, perhaps this humorous note from one of our best scientists (and puzzle experts) will help: “I guess it helps to know we are looking for seven. In that case, I see one on the left looking out, and in the middle four faces are clustered close together – in that group the brown nose of one (second from left) covers the right side of the face of the one crouched lowest. To the right is a small horse standing sideways, and above it is the rear of the seventh. Unless I am hallucinating.” Hope that helps. But if you still don’t see more than five or six horses (at least in part), then be reassured by the fact that you’re among the many who believe that the real number shown in this picture should be five.

Source: https://kids.niehs.nih.gov/games/riddles/illusions/how-many-horses