If a man were finding his way along a road, or through a wood, with no other mortal within a mile, the way in which he swung his arms, or otherwise behaved himself, would be of no consequence to any one but himself. If he met, now and then, another, his movements would have to be put under some slight and occasional restraint. If he were walking down a city street, his entire behavior would necessarily be subjected to discipline. If he were trying to force his way through a dense crowd, he would have to be content with very slow speed, and would have to use the utmost care and attention in the mode of his contact with the individuals around him. The limitations on his freedom of movement, on his chances of getting ahead with speed on his own business and on his personal comfort, would not advance in proportion to the increasing numbers about him, but would advance in a progressive and very rapidly increasing ratio.
If a man lived on a farm with no neighbor within a mile, the sanitary arrangements in and around his dwelling would have little importance except for his own family, and sanitary arrangements would be of very little importance at best under such circumstances. If he lived on a village street, sanitary arrangements would attain a certain importance. If he lived in a city they would become a leading interest. If he lived in a tenement in a densely populated part of a great city, sanitary arrangements would stand among the very first of the interests of himself and his neighbors. The interest and importance of sanitary arrangements would advance