Perhaps he would smell it, or see motion in the scrub around him.

In seeing motion all about, never doubt that I am there.

He also saw motion at the edges of the room.

Before long, he saw motion on the roadcoming up from the south.

Beyond the window, he saw motion on the garage roof.

He saw motion, a ripple on the water, but his eyes were too poor to make out anything more clearly.

He saw motion on the horizon and reached for his binoculars.

He rolled to the left, saw motion, and opened fire.

He could see only vague motion when someone behind the light moved.

In these cases, the eyes see motion, but the body does not sense it.