Walking and talking are two very great pleasures, but it is a mistake to combine them. Our own noise blots out the sounds and silences of the outdoor world; and talking leads almost inevitably to smoking, and then farewell to nature as far as one of our senses is concerned. The only friend to walk with is one who so exactly shares your taste for each mood of the countryside that a glance, a halt, or at most a nudge, is enough to assure us that the pleasure is shared. - C. S. Lewis