people have a tendency to associate colors with where these colors appear in nature.so,for example,without realizing it we associate soft shades of blue with the sky and sea.these associations make blue a calming color for most people. asuka obata runs a spa in kyoto,japan.all the walls of the salon are blue. Obata says,it is essential that we create a sense of peace and tranquility.the color bule helps us achieve this.