Chinese philosophers are on to something with their Yin and Yang concepts. Light balances dark, silence/noise, joy/sorrow, and in our case, mud offsets dust.
Yes, mud. Icky, gooey, sticky mud. Like cat hair, it latches onto anything it touches, finding its way from roads, yards, and pastures onto shoes and pant legs and into homes. It finds its way into the oddest places—a speckle stuck to a grocery sack, a chunk dropped by the door, a smear on a purse.