“Although today many are still of the opinion that images provide a means of communication that can overcome language barriers, the explanation of the way in which images can accomplish this by now takes one of two forms: the Egyptian and the Chinese way.
The Egyptian way today belongs only to art history. We believe that visual media such as paintings, sequences in films, etc. are “texts” which convey emotions and feelings that could not be expressed verbally: we cannot represent by mere words Mona Lisa to a blind person.
The meanings that such texts can express are multiple, because there is no universal code: the rules of representation (and of recognizability) for an Egyptian mural, an Arab miniature, a painting by Turner or a comic strip are simply not the same in each case.
It is true that some ideograms have been used as characters of a universal code, for instances many road signals; in the same vein we are using more or less universal pictograms (think of the schematic crossed knives and forks which signal a restaurant in an airport, or of the stylized “ladies” and “gentlemen” on public lavatory doors).
Sometimes visual signs are merely substituting alphabetical letters, as happens with semaphores or flag signals; sometimes a yellow flag meaning “contagious disease on board” simply stands for a verbal sentence (cf. Prieto 1966).
Likewise, the gestural languages of Trappist monks, Indian merchants, gypsies or thieves, as well as the drummed and whistled languages of certain tribes (cf. Le Barre 1964), are equally dependent on the model of natural languages.
As useful, convenient and ingenious as some of these systems of communication may be, they make no claims to being “perfect” languages in which philosophers might one day wish to compose a treatise.
Any language of images is based on the alleged fact that images exhibit some properties of the represented things. Yet in any representable thing there will always be a multitude of properties, and there are infinite points of view under which an image can be judged similar to something else. Moreover, “that a picture looks like nature often means only that it looks the way nature is usually painted” (Goodman 1968: 39).
We can see this by looking at the various versions of a semiotic apparatus (if not a true language) which remained alive for centuries and which flowered in the same period when the western culture was looking for perfect visual languages: the arts of memory (cf. Rossi 1960; Yates 1966).
An art of memory establishes at its expression-plane a system of loci (that is, of places in the literal sense of the word) which may be imagined as the rooms of a building or palace, or as an urban street or square.
This system of loci is destined to house a set of images, drawn from the same iconographical field, which will play the role of lexical units. The content-plane is given by a system of res memoranda, in other words, of things to be remembered, usually belonging to the same conceptual framework. In this way, an art of memory is a semiotic system.
For instance, in mnemonic systems like those presented by the Congestorius artificiosae memoriae by Romberch (1520), the Dialogo del modo di accrescerce e conservare la memoria by Dolce (1575), or the Artificiosae memoriae fundamenta by Paepp (1619), the system of grammatical cases is expressed (and thus recalled) by the different parts of the human body.
Not only is this a case of one system expressing another system; it is also a case where the two planes are (in Hjelmslev‘s sense) conformal. It is not arbitrary that the head stands for nominative, the chest, which can receive blows, stands for accusative, and the hands, which possess and offer, stand for genitive and dative, and so on.
This shows that a mnemonic image, in order to express its content easily, should evoke it by similarity. But no mnemonic system was ever able to find a univocal criterion of resemblance.
The criteria are the same as those that linked the signature to its signatum. If we look back and see (ch. 6) what Paracelsus had to say about the language of Adam, the Protoplastus, we see that he represented him as naming one animal on the basis of a morphological similarity (from which a virtue derived), while, in another case, the name derived directly from a virtue not manifested by the form of the object.
In other cases, the name that Adam gave reflected neither morphology nor causal relations, but was inferred symptomatically: for instance, the horn of the stag permitted us to infer the age of the animal from the complexity of its branching.”
Umberto Eco, The Search for the Perfect Language, translated by James Fentress, Blackwell. Oxford, 1995, pp. 168-71.