WEBVTT

1
00:00:03.500 --> 00:00:10.000
Illusions show us ways that we do not see the world the way it is.

2
00:00:10.000 --> 00:00:19.750
For example, the sizes of objects can change by simply moving where someone is in a scene.

3
00:00:19.750 --> 00:00:30.000
By studying illusions we can learn important aspects about how our visual system works, such as

4
00:00:30.000 --> 00:00:34.500
how we interpret depth and perceive size.

5
00:00:34.500 --> 00:00:44.000
Sometimes depth is perceived even when no depth is apparent as in the Müller-Lyer Illusion

6
00:00:44.000 --> 00:00:51.000
or depth is not perceived that is there as in the Ames Room.

7
00:00:51.000 --> 00:01:00.000
And this alteration in the perception of depth can change the perceived size of object.

8
00:01:00.000 --> 00:01:08.000
In addition, we do not just see objects but compare them to what is around.

9
00:01:08.000 --> 00:01:18.200
Both the perceived brightness and perceived size of an object can be changed by what is around it.

10
00:01:18.200 --> 00:01:27.000
So, let us end with a question.  Is seeing believing?