optical illusion-视错觉

Optical illusion is a kind of  interesting visual art that some of the visual artists work on the subject of the high & low ...

which part is higher and which part is lower?

It is very interesting to find the upper and the lower layer.

constellations on wall-墙上的星座

This is the visual art on the wall: Stellar Attraction. (on view at the Art Academy of Cincinnati's Pearlman Gallery from January 16-February 13, 2009) Copious amounts of the blank gallery walls have been left as breathing room around an impressive number of diminutive objects hung high above one's head and low enough to nearly touch the baseboards of the space. How one progresses through the space is less linear than exhibitions where work is hung consistently at a natural viewing height or displayed on pedestals. In their arrangement and in the treatment of the surfaces of the different works, Seeman interplays the order of the grid against the unpredictable compositions of constellations.

which is the higher and which is the lower ?哪个更高，哪个更低？

High and low
lithograph, 1947, 50.5 x 20.5 cm
 

In this print the same picture is presented twice over, but viewed from two different points. The upperhalf shows the view that an observer would get if he were about three storeys up; the lower half is the scene that would confront him if he were standing at ground level. If he should take his eyes off the latter and look upwards, then we would see the tiled floor on which he is standing, repeted as a ceiling in the centre of the composition. Yet this acts as a floor for the upper scene.

About the author

Maurits Cornelis Escher (17 June 1898 – 27 March 1972), was a Dutch graphic artist. He is known for his often mathematically inspired woodcuts, lithographs, and mezzotints. These feature impossible constructions, explorations of infinity, architecture, and tessellations.

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