Clarke on Two-Dimensional Life

"The planet was absolutely flat. Its enormous gravity had long ago crushed into one uniform level the mountains of its fiery youth-mountains whose mightiest peaks had never exceeded a few metres in height. Yet there was life here, for the surface was covered with a myriad geometrical patterns that crawled and moved and changed their colour. It was a world of two dimensions, inhabited by beings who could be no more than a fraction of a centimetre in thickness."

From Aurthur C. Clarke's Childhood's End, the author offers what reminds me of what Flatland must look like to a visitor, though I cannot imagine how a three-dimensional creature could survive under these pressures.