The good of a book lies in its being read. A book is made up of signs that speak of other signs, which in their turn speak of things. Without an eye to read them, a book contains signs that produce no concepts; therefore it is dumb.
Umberto EcoThe print does not always have the same shape as the body that impressed it, and it doesn't always derive from the pressure of a body. At times it reproduces the impression a body has left in our mind: it is the print of an idea.
Umberto Eco