Half as many people will not support half as many enterprises In a given geographical territory, half as many people will not support half as many such enterprises spaced at twice the distance. When distance inconvenience sets in, the small, the various and the personal wither away. Jane Jacobs, The Death and Life of Great American Cities densitydistancegeographybusinesseconomics
highdensityandovercrowding They hated both equally, in any case, and coupled them like ham and eggs, so that to this day housers and planners pop out the phrase as if it were one word, “highdensityandovercrowding.” Jane Jacobs, The Death and Life of Great American Cities densityurbanism
Four stages of competence An Idea en.wikipedia.org In psychology, the four stages of competence, or the "conscious competence" learning model, relates to the psychological states involved in the process of progressing from incompetence to competence in a skill. Unconscious incompetence Conscious incompetence Conscious competence Unconscious competence Good design can copy learningskillprogress