optical illusion

What he could see was wrong, like an optical illusion.

Perhaps, after all, the man was nothing more than an optical illusion.

There is an optical illusion about every person we meet.

Not just an optical illusion, but a real face looking back.

Some have put this down to simply being an optical illusion.

It was, of course, no more than an optical illusion.

The sun coming up and going down is one of the world's great optical illusions.

Her eyes suggested two further things, but either or both could have been an optical illusion.

I took it that this was an optical illusion of some sort.

Some people do not understand the concept of an optical illusion.

This was almost certainly the special type of optical illusion which can take place even though no one is actually looking at it.

On the third pass he realized it was no optical illusion.

It was weird, whether real or some kind of optical illusion.

All our ranks look like optical illusions to her, I think.

They appeared to support David's weight with a simple optical illusion.

Three different kinds of light, and all it added up to was an optical illusion.

She acknowledged that it might have been an optical illusion.

Others believe the inscription is in fact an optical illusion.

Sometimes it's more a bizarre optical illusion than a film.

Maybe it's an atmospheric effect, some kind of optical illusion.

And the thumbs, they both had that optical illusion on them.

"The concept was to make it look like an optical illusion," she said.

This is different from certain optical illusions, which do not work anymore once you can see it.

Now the big silver plane began to move back toward him, which was an optical illusion.

The area is home to an optical illusion known as a gravity hill.