Science and Citizenship
as he is apt somewhat wearisomely to remind us, are those of observation and classification, by comparison, generalisation, prediction, and verification by return to the concrete. To put it most briefly, the method of science differs from the method of other orders of thought in the necessity for arranging the various stages of investigation in such a way that two possibilities are always open. In the first place, it must be possible for every member of the scientific fraternity, present and future, to retrace and repeat every vital step in any and every investigation, from simple concrete observation right up to the largest generalisation. In the second place, it must be possible to return from the largest generalisation or the loftiest aspiration back to the concrete facts of nature, by a continuous series of steps, by an unbroken chain of evidence. This is the sacred Way of science. In most, if not all, the great religions of the East a peculiar sanctity attaches to the conception of the "way." That a mystic flavour should cling to Methodology will not therefore be surprising to those who hold that science is a culture-form of natural religion.
Having provisionally agreed upon our scientific criterion, we have two hundred and thirty-six definitive objects that exist in space and time under the designation of "City." From this proposition it follows that adequate precautions being taken cities can be seen. It is true that to see even a single