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Synesthesia and Homer's world

On the theory and history of synaesthesiae

L'Estetica Transmodale
di Enrico Cocuccioni

ON THE THEORY AND HISTORY OF SYNAESTHESIAE
by Tonino Tornitore

* Producer:

Every day everyone makes synesthetic metaphors, although most of them are dulled by now; it is easier to come across 'shrill colours' than 'coloured pitches': whereas once, during the Baroque period or in late Romanticism, it was the writers who coined innovative and daring expressions, today it is the press or advertisers who invent striking headlines 'for effect'. "Il silenzio è verde" - (silence is green) - is the title of an article in "La Stampa" newspaper of December 1989 about some types of plant that act as an effective anti-noise barrier). Objective synaesthesiae, on the other hand, are the productions of a few artists and of some scientists who, for example, synchronize colour with sound. (At the beginning of the 19th century Wallace Rimington, the British scientist, had constructed a special keyboard based on associations between colour and sound). Lastly, there are still fewer people able to see colours on hearing sound (colour-hearing), that is subjective or pure synesthetes (the Russian composer Aleksandr Scriabin, 1872-1915, noted that "on hearing certain sounds corresponding colours appeared in his mind" [Verdi]).

* Theoretician:

The linguist and rhetorician are designated to deal with figures of speech which call into question sensory interchanges, seeking to define their forms and functions (Ullmann); whereas artists and art critics, physicists and philosophers seek to establish (or to confute the existence of) objective links between data belonging to heterogeneous sensory spheres (from Aristotle to Newton, from Leonardo to Veronese). Doctors first, then psychologists sought, as the neurosciences seek today, to plumb the mysteries of the brain and, in particular, the sensory centres. A recent science programme ("Leonardo", 7.10.99) broadcast the discovery that the blind can "perceive" colour through the sense of touch; i.e. CAT (Computed Tomography Imaging) has revealed that touch stimuli also activate the sight centres in the brain of someone born blind (something that, in my opinion, supports the American neurologist Richard E. Cytowic's "mammalian" hypothesis [see infra p. ...]).

* Historian:

The historian may deal either with the history of the theories or with synesthetic practices (= productions); or, more usually, with both. I shall try to show by an example their potential divarication: whereas, a researcher into the history of literature would try to trace the earliest testimonies of synesthetic metaphors in literary texts, a historian of rhetoric would seek to discover the terminological, taxonomic attestations in treatises, or mainly in non-creative writing (the same goes for the objective and subective aspects).
So, there are from nine to twelve possible ways of tackling the forms of synaesthesia. I have studied two methods:-

starting with synchronic synesthetic metaphors (Tornitore 1990; for the historical aspect, cf. for example Tempesti, and Paissa); for subjective and objective synaesthesiae I am following a diachronic method (Tornitore 1986: Tornitore 1988), and in this paper I sall try to make a general excursus, albeit in a condensed and provisional fashion as the research is still in progress.
First, however, we should seek to give definite features to these impalpable and far removed entities, if not actually contrary to common sense. Aristotle in fact used the synesthetic aporia to clarify a logical absurdum: "in a sense one calls infinite whatever cannot be measured, like voice compared with sight"; if, in fact, the infinite is substance, then it is indivisible; but if it is indivisible, it is not infinite, if not in the same way as "voice is invisible", instead, if "the infinite is accidental, it could not be, inasmuch as it is infinite, an element of beings, just as an element of language is not invisible although the voice is invisible" (Physics, 204a 5-15 passim).

Theory:

For synaesthesia to take place two necessary or adequate conditions, which I shall call basic postuates, are required:
I) the simultaneous presence of two or more sensory fields (senses and/or sensations), real or virtual, distinct and diverse, from among the six conventionally classified (according to Ullmann's table, which distinguishes thermic from tactile sensations);
II) the above-mentioned heterogeneous sensory domains must be linked by a type of synthesis (from analogy to identification), and not of accumulation or parallelism.
This is the sieve proposed to sift the inter-sensory particles from pseudo-synesthetic tombac.
Without this preliminary basic epistemological operation: - of demarcation - it would not be possible to focus on the object of the enquiry, and therefore any approach to it (whether pragmatic, historical, theoretical) would be misleading. To find an indispensable common denominator let us start by investigating the theoretical implications of these postulates on an empirical basis.

1. POSTULATE

The better to frame the synesthetic phenomenon globally, let us begin by going back a step. We judge the physical state of the world according to current parameters, in brief, that is by hypothesizing matter as a gassy, liquid, colloidal or solid form; let us add two other 'physical' states: abstraction, with regard to the imaginary bodies which are abstract; and 'quintessence', for the senses (which strictly speaking, would not all be referable to a single state), according to this order of progressive rarefaction.
solid [= s], liquid [ = l], colloidal [= c], gas [= g], quintessence [= q], abstraction [ = a ].
Let us list the six quintessences
(i.e. the six senses - in deference to Ullmann, as mentioned):
Touch, Temperature, Taste, Smell sense, Hearing, Sight,
in progressive order from the least to the most differentiated sense; and lastly, still keeping to Ullmann's terminology to designate the components of a metaphor: font (for the sphere from which the metaphor is drawn) and the destination (the 'object' to be translated). Initially, one must distinguish in which case an element (like a sensation) is
the font and when the destination (usually recognisable grammatically, because the font is the attribute, and the destination is the substantive): for example:

(1) shrill red = font 'shrill' (therefore Hearing); destination = 'red' (therefore Sight) -> UV
(2) high pitched red = font 'red' (therefore Sight); destination = 'high pitched' (therefore Hearing) -> VU
More exactly:
(1) quintessence Hearing quintessence Sight
(2) quintessence Sight quintessence Hearing

Abbreviated to:
(1) quqv
(2) qvqu

By extending this microcombination to the whole range of interchanges (cambi stato)
and always keeping one of the terms (font/destination) =q ( that is, excluding, because not pertinent, those that are
'non-esthetic' (non-estesici), as in this expression:
'il dolore si scioglie in pianto' [= 1a] - 'the pain dissolved into tears'):

2) qn + g/1/c/s (= less rarefied states than q).
From this scheme the following four possibilities may arise: for example by putting 'n' = V as a fixed attribute (it would be incorrect to speak of a 'font', because it does not refer to metaphors, but to expressions used in the proper sense): the following examples would result:
(2a) 'sky blue' = qvg
(2b) 'sea blue' = qvl
(2c) 'gluey blue' = qvc ("blue glue")
(2d) 'material blue' = qvs ("blue material")
Obviously, we are in the presence of 'objects' to which one predicates a sensory quality, something that is not only logically permissable, but also referentially compatible. Therefore they have no synesthetic valence whatsoever.

Now, let us try to reverse the substantive/predicate order, using almost identicle examples (this time however qv is always a substantive, and we can rightly speak of a metaphor and 'blue' is the fixed destination):
(2A) 'airy blue' = gqv
(2B) 'fluid blue' = lqv
(2C) 'sticky blue' = cqv
(2D) 'blue matter' = sqv

These are some examples of changes in physical state (cambi di stato) to which a sensory datum has been applied. It is on this level of exchange that the true zero grade of synaesthesiae, especially in the presence of physically curious 'phenomena', like the well-known example of 'frozen words' in Rabelais's Pantagruel (IV, 55-56), which some synaestheologists, in the past, took for a milestone, if not actually as the incipit, in the history of synaesthesiae (cf. Tornitore 1988).

3) qn <-> a - aqn /qna (= the most rarefied state of q).
This matrix generates two types of expression, which, contrary to the previous example, are 'ambi-valent', in so far as they have both exchanged roles (font/destination) from sensation to metaphor, in the sense that either the colour itself becomes abstract or it is the abstraction which becomes concrete:
'blue fright' = qva
'feeling blue' = aqv

4) qn <-> qm = synaesthesiae
The interchanges of the senses therefore are none other than a particular form of changes of state, in which the following conditions, implicit in the matrix formula, are verified:
. 'n' = 'm': the sensations must belong to heterogeneous sensory domains; if it is obvious in expressions such as 'blinding colours', it is not out of place to stress it for oxymoronic forms, like 'sweet and sour', 'black light', 'deafening silence', in which it is true that two opposite sensations are associated, but that they belong to the same sensory sphere (from this one can deduce a more general rhetorical law: that linguistic synaesthesiae can be 'paradoxes', but never oxymora);

.. an organic state: 'vivid/bright red', 'rotten green' (slime-green)
.. an organic function, whether metaphorical ('sleep with relish' (sleep soundly), 'or devour it with one's eyes'), or real (sneeze, suddenly passing from dark to light);

. the 'common sensibles' of Aristotelian fame, that is the physical properties indirectly perceived by more than one sense (size, number, quantity, movement, shape): 'deep red', 'quick smells'; ambiguous synaesthesiae are a very important (linguistic) substrata, often based on the type of synecdoches in which the whole is used for a part: 'silence is golden', in which the 'golden' quality, by now synonymous with 'precious', does not exclude the colour yellow: 'of gold' / golden has (at least) two valencies (for example, one cannot exclude that in the future one may speak of the 'ducility' of gold and therefore of silence):
(preciousness -> aqu (= change in state) of gold)
(yellow -> qvqu (exchange of sense/meaning)

The expression may be understood either as a change in physical state (abstraction of qu: 'the precious quality of silence'), or as in a much less common type of synaesthesia VU ('yellow silence'): I refer to this type of pseudo-synaesthesia as 'ambiguous synaesthesia'. The following example may appear analoguous, because it is still a synecdoche in which the whole is used for a part:
'leaden silence'.
However, in 'leaden' there are (at least) two valencies, each referable to qx:

- silence 'heavy' like lead -> qTqU
- silence 'grey' like lead -> qVqU

Therefore, they differ from the previous example in that whichever valence is applied, it is nevertheless a sensory one; but precisely because of its non-univocity, it, too, is an ambiguous pseudo-synaesthesia, although less 'pseudo-' than in 'silence is golden'.

II POSTULATE

But for synaesthesia to happen, there must also be a second, simultaneous condition. An expression like:
(1) 'a hot, savoury and aromatic soup' / ('un brodo caldo, saporito e aromatico')
is a chain of sensations, linked to the same object ('soup') by parallelism and not by synthesis (analogy/juxtaposition) of sensory data which lead to an inter-change or reciprocal fusion.

Some rhetorical procedures may mask this parallelism, creating para-synesthetic effets as, for example, in these synecdoches in which a part is used for the whole (in contrast to those cited in the previous paragraph):
'a frozen bitter' (dry); 'a sweet white'
alluding in both cases to 'liqueur'. It is true that 'bitter' (dry) and 'frozen', like 'white' and 'sweet' are two pairs of heterogeneous sensory data, but the unifying link q (a ?) with q (c ?) (and qv with q /a ?/) is not a superimposed one, because as they are synecdoches, 'bitter' (dry) and 'sweet' are extrapolations of a sememe - taste, colour, - (held to be) prominent features pertinent to the object <liqueur> to which in fact they refer; and in so far as they are used as nouns, the objectivated sensations are open to any attribute, including a sensory one. So, 'a sweet white' is a brachylogism for 'a <wine> that is white <and> sweet', it is a parallelism analoguous to (1).

As a corollary to the above, in that it deals with objectivated entities open to any sensory attribution, it should be added that also attributes (held to be) anomalous have no synesthetic value:
"a white fly", "an enjoyable book" /(read with gusto)
are therefore (considered today) to be anomalies, but not synaesthesiae. In the second sonnet of Boccaccio's Rime one reads these lines: "a capelli femminei
giungea vesco / tenace Amor, ed ami aspri e acuti"
(to feminine locks, tenacious Love adds mistletoe and tart, sharp hooks).

The splendid head of hair of the beloved is as though it were strewn with mistletoe and interlaced with sharp hooks that fatally enmesh the lovers: 'aspro' (tart) forms with the following 'acuti' (sharp) an alliteration and a synonymic dittology, since Boccaccio certainly used it in its proper Latin meaning of 'pointed' (as in the proverb 'per aspera ad astra'); but, at the same time hinting at a savoury quality, although it may be unusual to allude to a hook as ('aspro') tart, it is perfectly congruous.

Let us now continue to analyse other pseudo-synesthetic examples, whose ambiguity stems from the rhetorical treatment to which the expression has been submitted. Leaving aside catachresis like ('white voices') or hackneyed metaphors such as ('warm voice'), in which the absence of an alternative synonym or overuse have made stereotyped, cancelling any inter-sensory trace. Let us begin with figures of speech where words are interchanged, as in Carducci's famous (or notorious) and easy example:
"divino del pian silenzio verde" - (divine plane of silent green).
This may be a figure of speech, or a violation of the 'ordo linearis',
... by accumulation = hypallage: 'green' is syntactically linked (by position) to the determinate (= 'silence'), but logically joined to the determinate, that is to the complement of specification; however, I consider this rendering to be unsatisfactory, in so far as the logical/grammatical alternative is inexistent (since both 'silence' and 'plane' are in the mascuine singular);
... by permutation - synchesis: this hypothesis, also treated by Mortara Garavelli, consists in a repeated exchange of anastrophes and hyperbata that recombine the alternation 'divine' - 'silence' and 'plane' with 'green' in a chiasmus adjective + substantive + substantive + adjective; although it is complete this interpretation seems to me to be too complex; in fact the expression could easily be resolved in another much simper figure:-
... by exchange = hyperbaton: the placing of the determinant 'plane' after 'silence' quickly dissolves the pseudo-synaesthesia into the straightforward: 'divine silence of the green plane'.
By removing the rhetorical 'artifice', the apparent qvqu reveals its true asynesthetic face. Were a pedant to accuse Carducci of an improper use of terms, he could easily defend himself by maintaining that he overlooked such banal expressions as 'the sister of hers': in Carducci's universe everything falls into place, the 'silences' are 'divine' and the 'planes' 'green' although not in that exact order. In line with this, even the unexceptional answer contains only a half truth, if not an actual alibi. Indeed, it would seem that the Author, after having tossed the synesthetic stone, hid his hand behind a rhetorical escamotage. Had he not intended to suggest this false synesthetic aura to his reader why would he have chosen to use this precise 'turn of phrase' out of all the possible alternatives, even only connotatively, even only as an additional semantic plus value? And it is in this sense that the synaesthesia "green silence" is ambiguous: as in "silence is golden", it is not (golden = precious) but at the same time it is, because the yellow of that gold cannot but shine in the reader's mind, as does 'golden hair', 'golden harvest', etc.
In 1879 a budding Carduccian scholar published Primo Vere, before a long series of collected poetic works. In one poem ("Connubii vespertini") (twilight unions) one reads these lines of verse:-
"La cascatella i piccoli echi suscita/ per li verdi silenzii" (The little waterfall's
faint echoes trill through the green silence).
This is an example of a (sensory) combination which is contrary to nature. The pupil has surpassed the master (in figurative licence). There is no artifice: 'green' refers only and properly to the 'silence' = synaesthesia VU. All the same the expression does not appear to be particularly shocking now, because the synecdoche (a part for the whole) is topical, 'green' stands for 'nature' and therefore "green silence" is equivalent to 'natural silence' (think of the heading of the newspaper article cited at the beginning). If the synocdoche is a figure of thought, no longer of speech, that is, an exchange of meaning but not of signification, it nevertheless remains a proximate figure which does not achieve total fusion between the two sensory spheres and, from the intersection resulting from their superimposition, as well as from linguistic usage, the 'normal' context can easily be reconstructed and roughly paraphrased as follows: the silence of the green countryside is broken only by the echoes of a small waterfall.
Another of Carducci's pupils composed these lines of verse, which are at least as famous as the master's:-
"La Chioccetta per l'aia azzurra/ va col suo pigolio di stelle" (The broody hen, about the blue threshing floor, goes with her cheeping stars).
In Pascoli's "Gelsomino notturno" a bold metaphor or allegory is examined: once the rural term 'Chiocetta' (Broody hen) has been substituted for the Pleiades, everything follows smoothly. The "threshing floor" is the sky, and the feeble/intermittent twinkling of the stars/chicks is logically rendered as the "cheeping" of the chicks. Therefore it is based on a sort of personification (constellation -> the hen) that acts as the keystone to the allegory resulting in a UV synaesthesia. But precisely because it is supported by this extensive metaphor, in this case too the 'normalisation' of the expression is very easy, given the simple transition from the auditory datum to the visual one.
In D'Annunzio and Pascoli's 'reduced' metaphor it is possible to recover a real, sufficiently univocal referrent. It is in this sense that I mentioned the insufficient fusion between the two sensory spheres in question: that is in the sense that the rhetorical synesthetic figure (or pretext) masks a content that is homo-sensory. Next, let us examine verse 1,377 in Euripides' Phoenissae:
"Il suono di una tromba lampeggiò come una fiaccola" (the Tyrrhenian clarion call flashed like a torch).
Note that the simile serves to describe the typology of the flashing, not to create Pascoli's type of proportionality (Chioccetta/Pleiadi) (Broody hen/Pleiades = pigolio/ luccichio): cheeping/twinkling):
the clarion call: [sonorous background] - (fiaccola) torch: [luminous background].
Between 'sound' and 'flash' there is no mediation, as an irrelative (irrelabile) short-circuit darts between the auditory datum and the visual datum (i.e. precisely a VU synaesthesia) that superimposes the visual sphere on the auditory one, leaving neither a residual margin nor substratum to which to turn as a reference, a 'normal' empirical or proven datum.

Therefore, for fusion or superimposition to take place between the two sensory universes there must be a corresponding relationship that may be either a bi-univocal correlation or a true and proper substitution, that is Xu equals Xm (as in a simile or correspondence), or Xn is Xm (as in a metaphor). All the other expressions are more or less complex rhetorical gambits that produce a fictitious synesthetic effect.

. there is a series of potential synesthetic stylistic figures of speech (only some of which we have examined) that goes from catachresis ('white voices') to the heterogeneous irrelate metaphor ('i rossi squilli di una tromba') (the red fanfare of the trumpet), endowed with a variable rhetorical effect, but perhaps also approximately or at least hierarchically quantifiable (equivalent to the determinate historical conditions that I put in brackets, not to undererate them, but because the horizon of these theoretical proposals is exclusively synchronic. However, the essential and complemental diachronic axis immediately evinces the need to distinguish between the hackneyed metaphor - 'warm voices' - from vivid, unpublished, metaphors like - 'green voices ' - whose success can basically be measured by the number of times they appear, which is in fact an historical-linguistic variable); within this graded continuum from the least to the most synesthetic, it is possible however to use some 'coupures' to distinguish the zero-synesthetic examples, like catachresis and worn out metaphors, from the para-synesthetic ones, being formal but not substantial synaesthesiae (a term I use to mean the resolution of the two postulates), and lastly, the synaesthesiae 'tout court', formal and substantial, which are in fact only metaphors (vivid or revived, that is the ex-worn out metaphors rejuvinated by a novel touch).
. whatever the order, or hierarchy, all the examples studied up to now are stock phrases, simple 'flatus vocis' not to be 'taken seriously' (or 'literally'); in short, for Mr Gabriele D'Annunzio silence is certainly not green, or is so only in the metaphorical sense.
'Correspondences' is the heading under which some of the most famous lines of verse in universal literature are classified:

Les parfums, les couleurs et les sons se répondent.
Il est des parfums frais comme des chairs d'enfants,
doux comme les hautbois, verts comme les prairies

["... in a deep and shadowy unity ... perfumes, sounds, colours correspond. Some
scents are fresh like a babe's skin, mellow as basoons, and verdant as meadows"].

After having stated that a relationship exists between the three distinct sensory domains (to which we shall return), Baudelaire maintained that some scents are, among other things, green, that is, they arouse an analogous impression, 'corresponding' to that aroused by green: that, not only has no referential correlation but is an additional proposition, let us say a third postulate that pilots this synaesthesia from the imaginary plane to the real one (note that also in this case the comparison - "like the meadows" - simply specifies the tone of the colour in question). This is a factual kind of assertion: for the poet certain scents are a certain type of green, as can be seen from the triple synaesthesia (CO, GO and VO) which takes up again the initial triple correspondence (although with reference to other sensory domains: O-V-U). We are no longer dealing with (rhetorical) figures of speech (Carducci's 'green silence') nor with a figure of thought (D'Annunzio's 'green silences', that is with 'modus dicendi', but with real synaesthesiae. Baudelaire announces the advent of a new expansion of sensitivity under the banner of inter-sensory perception, where to smell a scent means: to feel a 'real' shudder, (literally) to taste the sweetness of music, and to see a particular colour (for our statutary purposes, in order to establish a taxonomy, it is hardly worth mentioning the question of Hoffmann's source: however, it may serve to confirm the non-metaphoricity of the lines of verse).

Not content with this, he proposed to equate sound, colour and scent: this not only tells us that (to him) certain scents are green, but that in general sound, colour and scent mysteriously cor-relate to each other, and that this link is intrinsic to the nature of things, therefore potentially perceptible to everyone, and not necessarily linked to the 'sensiblerie' of the elect (or accursed).

Perhaps I have forced Baudelaire's text somewhat, but I have expanded upon it deliberately in an attempt to delineate, referring to the least possible number of quotations (a single expression in different contexts would have been ideal), the entire synesthetic phenomenology: the pseudo-synaesthesiae (Carducci's 'green silence'), the synaesthesiae 'in verbo' (D'Annunzio's 'green silences', 'in D major' (the silence corresponds to the colour green) and 'in intellectu' (perfumes are green).

Synoptically, I should denominate and demarcate the regions of the synesthetic universe as follows:-

pseudo-synaesthesiae: figures of speech that merely formally fulfil the two postulates thanks to a rhetorical form which achieves an artificial synesthetic effect; another famous example such as Dante's emblematic zeugma springs to mind: "parlar e lagrimar vedrai insieme" (speaking and crying you will see together) (the pseudo-synaesthesia consists in the elision of a 'verbum audendi' which the reader can easily discern and substitute);

metaphorical synaesthesiae (or synesthetic metaphors): figures of thought, in which the analogical-identificative link creates substantial and complete sensory (con-)fusion, whereby every meaningful reference disappears, leaving only an almost pure effect of 'depaysement' (disorientation) (I repeat: the frequent recourse to such metaphors can 'extinguish' or 'dull' them as metaphors, but that attributing a new meaning to them establishes a headword: this is what happened to Boccacio's above-mentioned 'asper', that has come to mean apart from 'aguzzo' pointed, also - and mainly in modern Italian - a sort of flavour);

objective synaesthesia: all the assertions of objective correlations (motivated or not) between heterogeneous sensory domains, without subjective involvement; this is the sphere par excellence of similitudes either presumed or held to be 'true';

subjective synaesthesiae: "associazioni di due sensazioni di natura distinta di cui una sola è obbiettiva" (association of two sensations, distinct in nature, of which one alone is objective) (cf. Beltran).

Strictly speaking only the last two can be said to be synaesthesiae tout court, the others being correspondences or rhetorical figures, although not only these, but also other strange phenomenologies like the changes of state (i cambi stato), first allowed Western imagery simply to be able to include in its mental baggage, i.e. to conceive of, synaesthesiae, and to challenge the homosensory evidence, and then to document and study them, and today actually to use them as a test bed and at the same time as one of the probes and intermodal hinges between the arts, human and natural sciences (neural, in particular).
The twofold programme of work that I have cut out for myself within this synaesthesiological universe:

The Histories

A history of objective synaesthesiae began many centuries before that of subjective synaesthesiae. Although it was precisely at the time the former reached a crucial turning-point that the latter began to take its first steps, and from then on, although parallel, the two stories intertwine at times; then, (perhaps), there is a prehistory as well as a history of objective and objective synaesthesiae.
Some years ago I studied the respective prehistories (Tornitore 1988); today, I maintain, thanks to the new critical material collected or to the criticism tout court showered upon me (and for which I am most grateful), that that work, although in need of careful in-depth revision, and the principle idea which inspired it are still valid: i.e., Western man, oppressed for centuries by the dominant Aristotelian homosensory view, would not be able to imagine synaesthesiae before that hegemony entered a profound crisis; that is, I do not believe that the first 'serious' inter-sensory attestations to be reported in a heterodox and philo-Baconian England were merely a historical accident.
At the present phase of research, I can only give some indications, more as a guide to my exploration than to the history of these ideas; a history that not only is not parrallel, but not even straight and monodimensional. I wish to make two points:

a) many of the current accounts (Ullmann, Schrader), precisely because they make out of every intersensory blade of grass a synesthetic bundle, and take the birth of these correspondences and changes of meaning back to the 'original' texts (Homer, the Vedas, the Bible ...); leaving non-Western cultures aside, since I ignore everything (starting with the language) to do with them; of the Homeric synaesthesiae, which are for the most part rhetorical, one of the most frequently quoted is the one in the Iliad, III, 152: about cicadas. Homer says they have an "òpa leiriòessan" /='liliaceous voice'/, therefore 'sweet, delicate' (in canto XIII the adjective in fact refers to the skin); but 'lily-voiced' is a synecdoche of the type the whole for a part and therefore, as seen above in 'leaden silence', ambiguous, because the object 'lily' can have various valencies (to limit ourselves to the heterosensory auditive ones: purity, softness) and therefore this is a pseudo-synaesthesia, and cannot be considered as an attestation in an historical excursus.

b) From the pervasion that the senses and sensations have in human life, it is easy to imagine that all the disciplines - the arts, the humanities, scientific and para-scientific - are or may be directly involved.

The prehistory of objective synaesthesiae probably goes back to the Pythagoreans (perhaps to the Egyptians, if not further - but, since I mean to keep within the bounds of Western culture, I shall start with Pythagoras who, according to Giamblico [Vita Pitagorica, XII], was "the first to call himself a 'philosopher'"). Pythagoras drew sustenance from the harmony of the spheres (Porphyry, 30, 5; Giamblico, XV, 65-6: "This harmony makes music fuller and purer than man's: in fact the motion and the circulations resulting from various uneven and different sounds among themselves, due to their rapidity, force, length of interval and yet reciprocally spaced according to a perfectly musical proportion are very harmonious as well as beautiful in their variety. From this music he drew nourishment and brought the mind back to orderly discpline ..."); besides feeding on celestial music, which implies a discrete change of state (materialisation of sound) calls into question a physical function (eating), what more directly interests us here is the correlation between the movement of the planets and music, which is a celestial variant of the presumptive discovery of the eighth tone in temporal music (attributed to Pythagoras again by Giamblico, who, in chapter XXVI recalls the famous legend of Pythagoras' visit to the smithy, where he sensed that the diversity of the sounds depended on the different mass of the hammers). The relationship between heterogeneous elements (weights, length of cord, acuteness of pitch) is perhaps the first step (which requires deeper examination) in the sphere of objective synaesthesiae.

The next step was taken by Aristotle: paradoxically he was the very one, the accomplice of common sense, who sunk the subjective synaesthesiae but founded the objective ones by instituting a relationship between taste and colour: "Just as the colours are the result of mixing black and white, so the flavours derive from sweet and sour, and each one of them exists in a relationship of more or less ... the mixtures that produce pleasure are however only those with a definite numerical proportion. So, fat is a sweet taste, salty and bitter are more or less the same, hot (spicey), acrid, sour, acid fall in between. The sorts of taste are almost equal to those of colour. There are seven of each type, if one supposes as is logical that grey is a black, and that yellow belongs to white as fat to sweet. Purple, red, green, blue range between white and black and all the others are mixtures of these (De sensu et sensil, 442a; scholars note that in fact eight colours and flavours are listed, but due to their relationship, in reality they should be considered to be six, since the same are also mentioned in De an. 421a 26; the number "seven" probably shows the influence of the musical model, which also reflects on the colours, odours and flavours [cf. Koucharski]). But the crucial stage of this history is marked, still keeping within the paradoxical sphere, by the one who was definitively to discount Aristotelian physics, Isaac Newton, (precisely in the second half of the 17th century). The British Scientist, also having to determine the number of colours of the continuum shown by the spectrum, at first adopted the pentachromatic scale of his friend Boyle, but then moved on to the heptachromatic, precisely by analogy with the musical octave. However, the capital innovation Newton introduced is another: the correspondence between sound/colour is no longer based on aleatory and external factors, as a mere number, but on the exact formulation of such a correspondence: the chromatic bands stand in a precise mathematical relationship to the harmonic tones: sounds and colours are equipollent 'sizes'. This intuition met with enormous success (and spread quickly - just think of "Newtonianesimo per le dame" by our Algarotti), partly thanks to the violent attacks directed at it - famous among these is Goethe's. One of the detractors of Opticks was a French Jesuit, Louis Bertrand Castel. In 1725 'Mercure de France' published a letter of his in which the physicist described an invention halfway between Vaucanson's well-known 'automates' and Duchamp's 'maccine celibi': the 'clavecin oculaire'. The inventor's declared purpose is certainly capricious, but also philanthropical, (as regards our commentary on objective synaesthesiae, this impulse was not due to his clerical status alone): the 'pianoforte per gli occhi' (pianoforte for the eyes) would also have enabled the deaf to enjoy the delights of music. The 'clavecin' however never worked, despite repeated efforts to perfect it mechanically, and although it had aroused favourable expectations in Europe's intelligentsia (Voltaire initially applauded the announcement of the undertaking). But it was not only its technical shortcomings that prevented the deaf from 'seeing' music. In reality the 'clavecin', beyond Castel's statements, did not have so much a philanthropic purpose as an heuristic one: it was to have been a tangible proof of the veracity of the traditional theory that the primary colours are three in number, and not seven as set out in the new Newtonian Opticks. Nevertheless, the idea of the first colour piano must have come to the French priest on reading Chapter XIV of Opticks, in which the British scientist had pointed out two sensational corrispondences, more than coincidences, namely: 1) that the primary colours diffracted by the prism number seven like the notes of the musical scale; 2) and that, like the notes, the colours differ from each other due to the exact proportion of the oscillation of the vibrant means. The 'clavecin' therefore represents the first attempt to apply 'aesthetics' to a scientific theory (although, as I said, founded on an optical pre-Newtonian paradigm). However, first the technical difficulties, and then Voltaire's cabals (and half of Europe's from Goethe to Leopardi) dashed it, as every other audiochromatic attempt has been, due to a structural flaw: "Those who imagine a music of colours and an instrument that delights the eye with their instantaneous and successive harmony, through the harmony of their combinations and variations, etc." overlook the fact that the pleasurable effect of music on the soul derives not from the harmony, but from the melody (Zibaldone, 1747 [20.9.1821]).

Even though the instrument failed to see the light of day, the concept behind the project, on the contrary, never set: from the Illuminists (Diderot entered the phrase 'Clavecin oculaire' in the Encyclopédie) to the German romanticists: in the sphere of 'Sturm und Drang', in particular Tieck and Runge, objective synaesthesiae ought to be magically reconverted into subjective ones. Actually, one of the new ideas which is growing on me is that the synaesthesiae are a little like those inventions or discoveries that in the course of history have been made, lost and made over again innumerable times. The crucible of the synaesthesiae at the turn of the 17th and 18th centuries was doubtless Germany (curiously the country the most hostile of Newton's discoveries - apart from Goethe, one can read the entry on colour in Hegel's Enciclopedia), where at least three crucial episodes are noted:
. the aesthetic reflections of the pre-romanticists: a productive field with a range of 360°, from the Grimms' research on languages, to Novalis' lively esoteric imaginings, from Wackenroder's correspondences between the arts, up to Hoffmann's 'fantastic' images, such as his 'alter ego' Kreisler, audiocolourist musician;
. in 1786, another and less famous Hoffmann, the physicist-mathematician Johann Leonhard (mentioned by Goethe on pages 392-3) began to make matching lists of "parallel ... phenomena" :
Indigo ......................... Cello
Ultramarine ................. Viola and Violin
Green ......................... Human voice
Yellow ......................... Clarinet
Bright red ................... Trumpet
Red-pink .................... Oboe
Red-crimson .............. Flute
Purple ......................... Hunting Horn

However, between the 18th and 19th centuries subjective synaesthesiae triumphed in full. Before rapidly reviewing them, I should like to recall one of the latest epiphanies of the notorious 'clavecin oculaire' (and therefore, in the objective nexus sound/ colour, that, note, is only one component, even though the richest and most famous, of the great sock of correspondences, that is exercised not only on the other senses - for example take Magalotti's research on scents - but also on the other disciplines - I confine myself to evoking Horace's 'ut pictura poesis', see Tornitore 1988), because such an epiphany has become contemporary history. In fact, at the end of September 1999 at the Theatre Carlo Felice in Genoa the first 'philological' performance of Scriabin's musi-chromatic score of Prometheus was finally realised, thanks to an electronic 'clavecin oculaire' (invented and built by DIST, the Genoese Athenaeum's Department of Music Informatics, under Antonio Camurri's direction, who succeeded where a few years earlier even Philips had failed). Castel's unrecognisable grandson synchronised the projection of luminous rays with the sonorous execution, seeking to reproduce a three-dimensional effect of the 'camera obscura' with acoustics within which to envelop the spectators/audience. Indeed, in the 18th century there were some who went so far as to complete Baudelairre's scale, by also flooding the hall with 'harmonised' perfumes (in the columns of Paris papers the performance of the 'Cantique des Cantiques' with sound, colour, perfume, dance, with the actors in variously 'intoned' drapery was famous). Today, the latest craze is to send pre-digitalised scents via TV and Cinema (as well as by Internet): the idea of Digiscent came to an American Company, to which the cyber review 'Wired' devoted the cover page in October 1999: in the bit world why not transform the scents into digital information? In fact the olfactory perception of our brain derives from the molecules which combine in a certain way with the determining particles in our olfactory system. Simply copy these molecules or produce similar ones; then select the basic aromas, which function like the basic colours of the rainbow: by combining the primary elements one can obtain all the others. Dexter Smith, Joel Lloyd Bellenson and John Williams have invented a machine designed to emanate the fundamental aromas and all their possible combinations, on activating digital impulses. Therefore also via the Internet. From here to the Cinema and TV equipped with scents it is but a short step (according to 'Wired'; Franco Carlini, who refers to it in his column 'Expresso' is more cautious).

Before the histories of objective and subjective synaesthesiae intersected and then continued partly together and partly separately (exactly as 'photographed' by Baudelaire's sonnet), the temporal bow of the pre-history or subjective synaesthesiae has a formidable arrow. In the Bible, as mentioned above, in Exodus 20:18 one actually reads: "et populus videbat vocem sonitumque buccinae". A prodigious synaesthesia of theophany. (Did God appear to Moses to dictate the Law to him?). It would appear to be so from Philo
Judaeus' account. But St Augustine hastened to extinguish the first synesthetic flame (will-o'-the-wisps) by explaining that the Prophet used the verb 'videre' (to see) in the figurative sense, as when we say 'see what is meant' instead of 'hear what is said' (Quaest. in Heptat. [Patr. Lat. XXXIV, 673]). One cannot exclude that one can find, especially in pre-modern heterdox cultures (as in Philo's), some synesthetic exploits (as a tribute to the course of history and its recurrences). It is certain however that those presented by the principle historiographers of the subject (like Schrader) are not to be considered as such, at least in the light of the above theoretical indications. In my view, one must wait for the beginning of the 17th century to signal the advent of subjective synesthetic history.

That the synesthetic flicker sparked in the bed of reflection on the senses is obvious, but that it should surface again in an English manual on instructing the deaf and dumb (this is why Castel's statement was not merely the result of pure philantropy) in the 17th century, not only amazes but makes one think that on the one hand this discovery has an air of being truly definitive, in the sense that precisely for a whole series of convergent circumstances, it could not but have been born there and at that time; and on the other, due to the peripheral sphere in which it was born, gives rise to the suspicion that there might be countless similar, or even more decentralised, spheres where this spark was struck (perhaps to be extinguished immediately).

Let us be methodical. In 1623, a strange and extraordinary person, Sir Kenelm Digby, met at the Court of Madrid a deaf mute who had learned to read the words on the lips of his interlocuter and therefore to converse, thanks to the teaching of a Spanish priest, Paolo Bonet, who was one of the first to have elaborated a method of teaching deaf mutes. Digby was very impressed and recounted the episode in one of his works which appeared in 1644: Two Treatises, in the one of which, the Nature of Bodies; in the other, the Nature of Man's Soule is looked into: in way of discovery of the Immortality of Reasonable Soules. He wrote he had "seen a person who could discern sounds with his eyes. It is admirable how often a sense compensates for the lack of another. Of this I have seen another strange example in a man ... who could hear with his eyes, if I may use this expression". The fact that Diogby not only laid stress on this expression, but that he accompanied it with a request to be allowed to take that licence seems to me the best proof of the fact that prior to the concept of 'visual audition' the term to express it did not exist. This passage in the Treatise on the Nature of Bodies (XXVIII, viii) did not escape the notice of the English Doctor John Bulwer, who took it as his starting point to perfect the technique of instructing deaf mutes (and therefore, in my view, this marks the beginning of the history of subjective synaesthesiae). He based himself precisely on that phrase that left Digby's pen, which he not only took very seriously but sought to support by appropriate scientific literature:
I have discovered that, among the different senses there is a sort of communance, and that on the human continent there exists a sort of 'Terra incognita' of occular audition [stress mine].... Having pondered on this great secret of nature, I have found that it is one of the most delicate facts of hidden knowledge that borders on the other cerebral ways, such as oral and dental audition, on which we possess a sufficient basis to arrive at a new art, and that it teaches us how to direct intelligible and articulated sounds to the brain by other channels than by the ear and the eye. Thus one can hear and speak. [Therefore it is a question of] teaching the eye to hear the sounds of the words, if such an expression can be used [note the repetition of Digby's cautious formula]. Of course, both the phenomenon and the expression are totally new and might seem exceedingly strange to those who either do [not] know about the existence of the communance of the senses, or have not reflected on it. It is admirable how the objects of one sense can be known by another, and how often a sense can compensate for another in its absence. In fact, light can be felt, scents can be tasted, the appetising savour of food can be perceived by the sense of smell, size and form can be heard, and sounds can be seen, felt and tasted. Indeed, it would seem that it is not absolutely necessary that the sensations be made by one organ, deputied for the purpose, but that a sense can be exercised by the organs of another, through an exchange of sensory functions, that, on careful examination would also convince the most skeptical of the existence of a communance between them.... We, in fact, see that touch is the basis for all the rest. And therefore Campanella in his ingenious book De sensu rerum demonstrates that all the senses have the purpose of touch, but the sensors and the manner to feel differ, which he finds in all the senses, proving that every sensation is produced by contact.... That the smells can be tasted and the taste of food smelt is not so strange if we consider the conformity that exists between the two senses of smell and taste. Doctors who write about the senses find them all to be in conformity and in fact it has happened that the loss of one of them can bring about the loss of another....
If all the senses, then, were to be defective, except for touch (which cannot be entirely eliminated without the cessation of life), the virtue of all the senses would flow into it to make it the king of the senses (that cannot be dethroned), so accurate and precise as to be able to act on behalf of all the others.... Servius, in his tract De unguento armario, [speaks] of a man, who, having lost his sight, nevertheless saw with his nose.... The defective ear of the deaf may be substituted by the office of the eye, as the impaired eye of the blind, by the office of the ear. Thus the ear can therefore see, and this would not appear to be so paradoxical if we consider the consensus of audible and visible things, so elegantly described by my Lord Bacon in his Natural History ... since hearing has a great affinity with the organ of sight. They both have a common faculty, and the extremity of the auditive passage, where the nerve ending joins the air there, corresponds to the crystalline. In the same way those parts that surround the involution of the ear correspond to the sight of the eye and to the other parts around the crystalline. And I should like to know why Gordonio ... in his description of the auditory organs, where he speaks of the sickness of the ear, attributes to the ear a concave optic nerve. His commentator confesses that he fails to see for what reasons he does so and until someone goes further into his thought, we may suppose that he was an occult friend who believed in auricular vision. Now the expression to hear sounds with the eye can be used, because it cannot be denied that hearing is none other than the exact perception of movement, since movement and sound are not different entities, but one and the same thing.... This is proved by the observation of sounds, which follow the laws of movement, as every effect of theirs can be demonstrated with the principles and with the proportions of movement.... Besides, it can be proved by the simple experiment of perception of music by means of a stick. In fact a deaf person is able to perceive it in this way. Now, as sound, or articulated movement, can be perceived by the eye, so hearing is like seeing and hearing seeing. Therefore, it is not incorrect terminology to state that the eye can hear, since it can perceive the object proper to hearing, and to substitute for the function of the ear to judge the sound, which is a movement. And what we call sound which makes speech audible is none other than movement ... and can be regarded as a common sensible (comune sensile) and be perceived by more than one of the exterior senses.... One may object: 'There are however many movements without any sound, because one can move a hand or any other part of the body without producing a sound'. That may also not be so, as we have reason to suspect that there may be a sort of sound in every movement ... even though it may not be perceived, being drowned by the louder noises that surround it. And we are encouraged by our art to ask the question: whether the ear is truly the only judge of sound? Further: since there are peoples without ears who can also hear very well, then it is really true that the articulated movement does not always require an audible sound, but a visible one at least.... If we, with the help of God, can with this art have such success that a deaf person can be brought to enjoy with the eye the benefit of the ear, that is that the eye may substitute for the ear, allow me then to dispute whether he can smell with the eye or not; because we are not so advanced in this subject as to deceive others with vain philosophy and fine words".
The length of this quotation, shortened to the essential, serves to give an idea of the awareness, wealth and maturity of John Bulwer's crucial contribution, from the Philocophus, or the Deaf and Dumb Man's Friend published in London in 1648 (the citation is taken from G. Ferreri's translation into Italian, pp. 10-56 ff.), although it still retains strong traces of uncertainty and of perplexity regarding the phenomenon. Just note the final warning: "But I do not pretend to impose any fantasy" on holding as true, philosophically and physiologically true, "the expression of the sounds heard by the eye"; indeed, if the method of instruction and rehabilitation of the ear-impaired patients functions, on the theory that supports it allow me once more to make an inventory, further research to frame the theory (since, strictly speaking, the primary objective of the little work is didactic).
It will be neither an easy, nor a short term task. Bulwer's theoretical framework is based on the assumption (Aristotle's, obviously) that words, as sounds, "are none other than movements", and the movements as 'common sensibles' can also come under the control of sight; however he overlooked that the 'articulted movements' are due to the vibration of the vocal chords in the resonance chamber of the mouth organ, and the vibrations are not perceptible to the eye. Therefore this could be neither the highway nor the way forward for the didactic instruction of deaf mutes (in fact one must have recourse to touch for the deaf person to be able to associate movement with the specific vibrations of the sounds of the letters of the alphabet) nor for audiocolourism. In fact it will reappear, in the scientific context, in a very different guise, although still under the heading of 'diversity', of physiological anomaly: when in the year 1812 (that is more than a century and a half later), an albino German student was to graduate in medicine with an auto-descriptive thesis on albinism, some of which phenomena will be considered (another half a century later) to be probable stigmata of 'colour-hearing'. What happened at the same time in other fields of knowledge will form the subject of my next general historical study on synaesthesiae.
To come to the present. Following the exponential development of the neurosciences and of the research on the computed tomography of the brain, the nineteenth-twentieth century view, which considered the synesthete a 'monstrum', an anomaly, whether a benign or evil one, was toppled (for Nordau and the positivist anthropoligists it was a sign of the 'degeneracy' of the race). Today psychologists and neurophysiologists agree in holding them all to be potential synesthetes, even though the explanations differ:
* according to the theory of amodal transfer, our brain is a system of "rings within rings" (Pierantoni), so that as soon as a sensory datum enters the network, it is like a stone thrown into a pond: the ripples spread concentrically into all the sensory districts, activating the other sensations as well; the fact that we are not aware of it is due to the limited awareness we normally have of the intense work that takes place at the cerebral level, in contrast to some synesthetes who, in given conditions, succeed in feeling this on-going intersensory background;
* according to psychologists (L.E. Marks in particular) we all have a switchboard interconnecting the various senses, normally dormant, even if at birth it is there in reserve (in fact the phenomenon is more widespread and pronounced in children), and can also be artificially reactivated with certain hallucinogenic substances;

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Milan, November 1999.