All happy cities resemble one another, to paraphrase what Tolstoy famously observed of families, but each melancholy city is melancholy in its own way. The saudade of Lisbon, the tristeza of Burgos, the mufa of Buenos Aires, the mestizia of Turin, the Traurigkeit of Vienna, the ennui of Alexandria, the ghostliness of Prague, the glumness of Glasgow, the dispiritedness of Boston share only on the surface a common sense of melancholy.
Not every city has this spirit, but I've visited a few that do for long enough to recognize it. Lisbon, Prague, Krakow.
Someday, I will go to Istanbul.
[Pamuk suggests] Istanbul is haunted by another Istanbul, a shadowy presence in the shadows. He sees the city in black and white, mirrored in the ancient engravings and old photographs that illustrate the book — a city in which ruined buildings conjure up the ghosts of their former selves and stately monuments insinuate their future collapse. Through the descriptions of other writers — several Turkish masters, various traveling foreigners — Pamuk parades yet more double-images of the Istanbul he knows. As seen by the poet Yahya Kemal or the historian and encyclopedist Resat Ekrem Kocu, by Gerard de Nerval or Gustave Flaubert, Pamuk's Istanbul keeps unfolding like a series of Rorschach tests, multiplying its ink-stained ghosts and tempting the reader with potentially infinite interpretations.
Consider the paving stones beneath your feet.