Typography is an instrument of communication. It must communicate clearly in the most urgent form. Clarity must be emphasized because, in comparison with prehistoric pictographs, it is the essence of script. Our intellectual attitude to the world is individually precise (this individual precision is today changing to collective precision), as opposed to the old individually and later collectively amorphous forms. Therefore above all, unambiguous clarity in all typography. Legibility communication must never be allowed to suffer for an aesthetic code adopted in advance. (Whitford; Masters and students p.186)
Link: Typography of the Bauhaus