The transmission of ancient texts follows what may be called the painted ancient statue effect. It is a well-known fact that most statues of ancient Greece and Rome as well as those which were still being carved in the medieval West were not left blank as we see them today in museums, but were lavishly painted over in natural pigments which have since faded out.
The statue is there, but something is missing. The presence, intention and splendour of a world long vanished survive, but it’s just a trace. That world may never be experienced through its relics, however beautiful and exemplary they may be.
Ancient texts are like these statues. A few facts: the ancient world produced far more written works than the ones which have come down to us, to the effect that what survives today is a sample of the body of texts that used to circulate in the classical world; nearly all of the works which survived Late Antiquity (3rd-7th centuries AD) were reunited during the Renaissance and handed down to us, so that very few classical texts were lost during the Middle Ages.
Our literary access to the classical past is like looking at sculptures by Lysippus, Phidias or Praxiteles, all famous sculptors of ancient Greece, and imagining the world which could house such treasures and sustain the people who marvelled at their beauty. That road is partially blocked by our imperfect knowledge and faulty ability to see these sculptures arrayed in painted glory and the eyes that gazed upon them.