Which Line is Longer?

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Despite the vertical appearing longer, the two lines are the same length. This visual illusion is common to most humans. This illusion happens in the real world, with a telephone pole or tree appearing taller when vertical than when laying flat on the ground.

There are cultures where perpendicular lines are rare, such as desert tribes who live in rounded huts without perpendicularly angled tables and boxes and television sets. The people of these societies are less likely to be fooled by the above illusion.

This illustrates that culture does influence one's visual perceptions, even of such 'objective' things as lines and angles.

It is interesting that it is those experienced with perpendicular lines that fall for this illusion. Most would assume it would be the inexperienced that are more likely to be tricked. main



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