“Take proper care of your monuments and you will not need to restore them. A few sheets of lead put in time upon the roof, a few dead leaves and sticks swept in time out of a water-course, will save both roof and walls from ruin. Watch an old building with an anxious care: guard it as best you may, and at any cost from every influence of dilapidation. Count its stones as you would jewels of a crown; set watches about it as if at the gates of a besieged city; bind it together with iron where it loosens; stay it with timber where it declines; do not care about the unsightliness of the aid; better a crutch than a lost limb; and do this tenderly, and reverently, and continually, and many a generation will still be born and pass away beneath its shadow.
“…I must not leave the truth unstated, that it is again no question of expediency or feeling whether we shall preserve the buildings of past times or not. We have no right whatsoever to touch them. They are not ours. They belong partly to those who built them, and partly to all the generations of mankind who are to follow us. The dead have still their right in them: that which they labored for, the praise of achievement or the expression of religious feeling, or whatsoever else it might be which in those buildings they intended to be permanent, we have no right to obliterate. What we have ourselves built, we are at liberty to throw down; but what other men gave their strength, and wealth, and life to accomplish, their right does not pass away with their death; still less is the right to the use of what they have left vested in us only. It belongs to all their successors. It may hereafter be a subject of sorrow, or a cause of injury, to millions, that we have consulted our present convenience by casting down such buildings as we choose to dispense with. That sorrow, that loss we have no right to inflict.”
John Ruskin, The Seven Lamps of Architecture, Chapter VI, “The Lamp of Memory,” Sections XIX and XX.