For Greeks and Romans, paper (the flat papirus invented by Egyptians) was a luxury. So they developed what is called "The Art of Memory" (mnemotechnics).
The idea was this: the man (or woman: remember Aspasia, the hetaira, taught Pericles the art of rhetoric, closely related to the Art of Memory) who was going to give a speech (dis-course, for those who can understand latin languages) imagined a building. The building had a central court, and rooms all about it. So (AS WORDS ARE IMAGES) the man giving the speech just went through his IMAGINARY building leaving certain objects in each room. To remember, he just had to re-course (walk again over) the said imaginary building, collecting the objects he had left in each room, to RE-COLLECT what he wanted to say.
Now to the beautiful part: in that imaginary city of individually built memory buildings, there where COMMON PLACES (PLAZAS, SQUARES). In those common-places, all the inhabitants of the said imaginary city (all of us live in imaginary cities, because cities are just the places where we are ourselves, and by that I mean we as ourselves, with our personal memories) could MEET. That is why they are COMMON places. Tiananmen is one, the Red Square is another, the Mall before the Lincoln Memorial another... the little-intimate-know-by-so-few Plaza Bolívar counts too... in spite of the Esquina Caliente, as Fascist as possible a way to rob a town of it´s own memory as history registers!
So please, don´t fear commonplaces. There we can meet...
(For more information, see Frances A. Yates, "The Art of Memory". It´s a great book, but very difficult, girls and guys... I only got thru 4 chapters before going mad!).