Roundness seems to be a universal human pleasure.

Vartanian and collaborators slid people into a brain imaging machine, showed them these pictures, and asked them to label each room as “beautiful” or “not beautiful.” In a study published earlier this year, they reported that test participants were far more likely to consider a room beautiful when it was flush with curves rather than full of straight lines. Oblong couches, oval rugs, looping floor patterns–these features got our aesthetic engines going.

“In other words,” says Vartanian, “we prefer curves because they signal lack of threat, i.e. safety.”

source: fastcodesign.com