Topics Perception

Question I was looking at earlier questions in your Perception section and was intrigued by Prof. Moore's answer to the one of the car driving down the road and appearing to get smaller with distance (http://www.askphilosophers.org/question/548). He said that the size of the real car is an intrinsic property of the car, but the size of the apparent car is a relational property of the real car, and subtly so. I wish he would explain this subtlety, because I just don't get it. I can see that the distance between the car and the observer is a relational property: the relation is the distance, and its terms are the apparent car and the observer. But how can the apparent size of the car be a relation? The apparent car has an apparent size which, it seems to me, is just as much an intrinsic property of the apparent car as the real size of the real car is an intrinsic property of the real car. I am also fascinated by the question that he did not answer: at what distance must the car be for us to see its real size? Please tell me!

Accepted:
August 15, 2008

Comments

There are real cars, with real sizes -- five feet high, twelve feet long, for example -- and they would be these sizes even if there was no observer to notice them. When a real car appears to an observer to be smaller, or larger, than it actually is, we can speak of its apparent size as opposed to its actual size; but the notion of an apparent size only makes sense in relation to an observer to whom the car appears to be one size rather than another. That is why Prof. Moore considers the real size of a car to be an intrinsic property while the apparent size of a car is a relational property.

The distance between a car and an observer does not translate into a difference in the apparent size of that car to that observer since a distant car may appear to be its real size to some observers, and a nearby car may appear to be bigger or smaller than its real size to some observers. Thus, there is no general answer to your question about what distance a car must be in order for us to see its real size. Some people, in some circumstances, are very good at seeing the real size of a car at a distance; others are not.

Finally, it is important to remember that there is no such thing as an apparent car. If someone seems to see a car of a certain size when there is in fact none to be seen, that is a fact about the observer -- not an intrinsic fact about a non-existent car nor a fact about a relation that exists between an observer and a non-existent car. The temptation to reify 'apparent objects' is partly responsible for the sort of confusions that you express in your question.