○○○Albert Einstein⪢⪢
I am enough of an artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.
→ encircle
#quote
http://qindex.info/i.php?x=20318
○○○classify⪢⪢
Another way topologists classify things are in terms of the number of distinct loops you can draw around the surface of a shape.
http://qindex.info/i.php?x=5172