LOOKAGAIN

A tiny museum for your visual system

YOUR EYES
ARE NOT
CAMERAS.

They guess. They compare. They fill in gaps. Meet ten illusions that show your brain at work.

Enter the exhibits
SEE IT · DOUBT IT · LEARN WHY · SEE IT · DOUBT IT · LEARN WHY · 

01 / Peripheral drift

Still image. Moving feeling.

Keep your eyes moving gently around the picture.

Answer concealed

Look first. Trust your guess. Then open the explanation.

02 / Simultaneous contrast

Same gray. Different worlds.

Drag the slider. The center squares never change.

Answer concealed

Look first. Trust your guess. Then open the explanation.

03 / Ebbinghaus illusion

Which orange circle is bigger?

Make your guess, then remove the neighbors.

Answer concealed

Look first. Trust your guess. Then open the explanation.

04 / Negative afterimage

Make a color that isn’t there.

Ready?

Press start, then keep your eyes on the dot.

Answer concealed

Look first. Trust your guess. Then open the explanation.

05 / Necker cube

A cube with two front doors.

Tap the cube. Try to make its depth flip.

Answer concealed

Look first. Trust your guess. Then open the explanation.

06 / Impossible object

A staircase with no escape.

Follow one edge. Where does ‘up’ stop?

Answer concealed

Look first. Trust your guess. Then open the explanation.

07 / Café wall illusion

Straight lines, crooked feeling.

Look across the gray lines. Are they parallel?

Answer concealed

Look first. Trust your guess. Then open the explanation.

08 / Müller-Lyer illusion

Two lines. One suspicious ruler.

Compare the horizontal lines, then remove the arrowheads.

Answer concealed

Look first. Trust your guess. Then open the explanation.

09 / Kanizsa triangle

A triangle drawn with nothing.

Find the bright triangle, then break its corners apart.

Answer concealed

Look first. Trust your guess. Then open the explanation.

10 / Lilac chaser

A green dot that never existed.

Keep your eyes on the center cross and notice the moving gap.

Answer concealed

Look first. Trust your guess. Then open the explanation.

The big idea

Seeing is an
active process.

Your brain receives incomplete signals and builds its best guess of the world. Illusions are not failures—they are clues to the clever shortcuts that usually help you see quickly.