Plotino - Tratado 29,3 (IV, 5, 3) — A afecção de um intermediário não é a condição da vista (1)

3. Una prueba decisiva de que la forma de los objetos no es transmitida a la vista por intermedio del aire, afectado gradualmente, nos la da el hecho de que, por la noche y en la oscuridad, vemos el fuego, los astros y las formas de éstos. No podrá decirse, verdaderamente, que las formas originadas por ellos han entrado en contacto con nosotros a través de la oscuridad, porque en este caso no habría oscuridad, al iluminar el fuego sus formas. Por otra parte, aun en la más profunda oscuridad, ya ocultos los astros y sin que provenga de ellos luz alguna, vemos el fuego de los faros y el de las torres que se muestran en las naves. Si se afirmase que este fuego atraviesa el aire, contrariamente a lo que testimonian nuestros sentidos, sería entonces necesario que tuviésemos la visión de una forma oscura en el aire, pero no la del fuego mismo, que es lo que claramente se percibe. Si vemos, por tanto, lo que está más allá de un medio oscuro, veremos todavía mejor cuando no se da este medio. Y si se objetase a esto que no hay realmente visión cuando no hay un medio, tendríamos que contestar que no es esencial aquí la falta de un medio, sino en mayor grado que se haga desaparecer la simpatía del animal universal consigo mismo y la que existe entre todas sus partes, que habrán de constituir una unidad. Pues parece que la sensación existe, porque este animal — esto es, el todo — simpatiza consigo mismo. De otro modo, ¿cómo un objeto podría sufrir la influencia de otro, y sobre todo de un objeto alejado? Tendríamos que examinar también, para el caso de que existiese otro mundo y otro ser animado no tributario del nuestro, si un ojo, situado en la convexidad del cielo, podría contemplarlo a una distancia conveniente, o bien si ese mundo no existiría para él . Pero dejemos la cuestión para más adelante.

Traigamos aquí otra prueba de que la sensación visual no tiene lugar por el hecho de que el medio sea afectado. Porque si el aire fuese afectado, lo sería necesariamente a la manera de un cuerpo, esto es, a la manera como la figura se imprime en la cera; en cada parte de la impronta quedaría impresa también una parte del objeto visible, hasta tal punto que la parte de la impronta que está en contacto con el ojo recibiría del objeto visible una parte igual a la de la pupila. Ahora bien, lo que se ve es el objeto en su totalidad y todos cuantos están en el aire lo ven, ya lo miren de frente u oblicuamente, de cerca o por detrás, y siempre que nadie se interponga. De modo que cada parte del aire contiene verdaderamente la forma visible total, pero no como estado de un cuerpo sino según la necesidad de la simpatía en el animal universal, la cual se refiere a las almas por ser de naturaleza más alta.

III. Une forte preuve que les formes des objets sensibles ne sont pas vues parce que l’air, étant affecté, les transmettrait en quelque sorte de proche en proche, c’est que dans l’obscurité on voit le feu, les astres et leurs figures. Personne ne saurait prétendre que, dans ce cas, les formes des objets, étant imprimées à l’air obscur, sont transmises jusqu’à l’œil; sinon, il n’y aurait pas d’obscurité, puisque le feu éclairerait en transmettant sa forme. En effet, dans une obscurité profonde où l’on ne voit point la clarté des astres, on aperçoit le feu des signaux et des phares. Si quelqu’un, se mettant en opposition avec le témoignage de la sensation, prétend que dans ce cas même le feu pénètre l’air, nous lui répondrons que la vue devrait alors distinguer les plus petits objets qui sont dans l’air au lieu de se borner à apercevoir le feu. Si donc on voit ce qui est au delà d’un milieu obscur, on le voit bien mieux quand il n’y a pas de milieu. — Mais, nous objectera-t-on peut-être, lorsqu’il n’y a pas de milieu, on ne voit point. — C’est, non parce qu’il n’y a pas de milieu, mais parce que la sympathie de l’animal [universel] est alors détruite, puisqu’elle suppose que les parties de cet animal ne forment qu’un seul être. Il semble en effet que la sensation a pour condition générale que l’animal universel soit sympathique à lui-même; sans cela, comment une chose participerait-elle à la puissance d’une autre chose dont elle serait très éloignée?

Voici encore une autre question [relative au même sujet] qui nous paraît digne d’examen : S’il existait un autre monde et un autre animal qui n’eût aucun rapport avec notre monde, si de plus il y avait à la surface du ciel un œil qui regardât, apercevrait-il cet autre monde à une distance modérée ou bien n’aurait-il aucun rapport avec lui? Mais nous traiterons cette question plus loin [§ 8]. Maintenant, nous allons donner une nouvelle preuve que la vision n’a pas lieu parce que le milieu est affecté.

Si l’air était affecté, il éprouverait une affection matérielle, semblable à la figure imprimée sur la cire. Dans ce cas, une certaine partie de l’objet serait figurée dans une certaine partie de l’air ; par conséquent, la partie de l’air qui est voisine de l’oeil recevrait une partie de l’objet visible d’une grandeur égale à celle de la pupille. Or, on voit l’objet visible tout entier; tous ceux qui sont dans l’air l’aperçoivent également, soit qu’ils le considèrent de face, soit qu’ils le regardent de côté, soit même qu’ils se trouvent placés les uns derrière les autres, pourvu qu’ils ne se fassent pas obstacle les uns aux autres. Ceci prouve que chaque partie de l’air contient l’objet visible tout entier: or cela ne peut s’expliquer par une affection corporelle, mais par des lois plus relevées, propres à l’âme et à l’animal qui est partout sympathiqueà lui-même.

USELESSNESS OF AIR AS TRANSMITTING MEDIUM PROVED FROM SIGHT OF OBJECTS AT NIGHT.

3. A strong proof that the forms of sense-objects are not seen merely because the air, on being affected, transmits them by relays from point to point, is that even in darkness the fire, the stars, and their forms may be seen. In this case no one would claim that the forms of the objects, being impressed on the obscure air, are transmitted to the eye; otherwise, there would be no obscurity, as the fire, while transmitting its form, would illuminate. Indeed, in the profound obscurity in which the light of the stars is not seen, the fire of signals and of light-houses may be perceived. Should any one, in opposition to the testimony of his senses, claim that even in this case the fire penetrates the air, "he should be answered by having it pointed out to him that in that case human vision should distinguish the smallest objects which are in the air, instead of being limited to the perception of the fire. If then we see what is beyond a dark medium, it would be much better seen without any medium whatever.

ABSENCE OF MEDIUM WOULD INTERFERE WITH VISION ONLY BY DESTROYING SYMPATHY.

It might indeed be objected that without medium, vision ceases. This occurs not because of the lack of medium, but because the sympathy of the (universal) organism is in such a case destroyed since a medium presupposes that all the parts of this organism together form but a single being. It would indeed seem to be a general condition necessary for sensation that the universal organism be sympathetic with itself; otherwise, no one thing could participate in the power of any other thing that might happen to be very distant.

VISION IS NOT DEPENDENT ON THE AFFECTION OF THE MEDIUM.

Here is another important (related) question. If there existed another world and organism which had no relation with our world, and if on the surface of the sky was an eye that was looking, would it perceive this other world at a moderate distance, or would it have no relation thereto? This question will be considered later. Now however we shall give a further proof that the medium has nothing to do with vision. If the air were affected, it would experience a material affection, similar to the figure impressed on wax. In this case, a certain part of the object would be impressed on a certain part of the air; and consequently, the part of the air nearest to the eye would receive a part of the visible object, and this part would be of a size equal to that of the pupil. Now a visible object is seen in its entirety, and all those who are in the air equally see it, whether they behold it from the front, or side, or whether they be one behind the other, without however forming mutual obstacles. This proves that every part of the air contains the entire visible object. This cannot be explained by any corporeal affection, but by higher laws, suitable to the soul, and to the (universal) organism which everywhere responds to itself.

3. For the most convincing proof that vision does not depend upon the transmission of impressions of any kind made upon the air, we have only to consider that in the darkness of night we can see a fire and the stars and their very shapes.

No one will pretend that these forms are reproduced upon the darkness and come to us in linked progression; if the fire thus rayed out its own form, there would be an end to the darkness. In the blackest night, when the very stars are hidden and show no gleam of their light, we can see the fire of the beacon-stations and of maritime signal-towers.

Now if, in defiance of all that the senses tell us, we are to believe that in these examples the fire [as light] traverses the air, then, in so far as anything is visible, it must be that dimmed reproduction in the air, not the fire itself. But if an object can be seen on the other side of some intervening darkness, much more would it be visible with nothing intervening.

We may hold one thing certain: the impossibility of vision without an intervening substance does not depend upon that absence in itself: the sole reason is that, with the absence, there would be an end to the sympathy reigning in the living whole and relating the parts to each other in an existent unity.

Perception of every kind seems to depend on the fact that our universe is a whole sympathetic to itself: that it is so, appears from the universal participation in power from member to member, and especially in remote power.

No doubt it would be worth enquiry - though we pass it for the present - what would take place if there were another kosmos, another living whole having no contact with this one, and the far ridges of our heavens had sight: would our sphere see that other as from a mutually present distance, or could there be no dealing at all from this to that?

To return; there is a further consideration showing that sight is not brought about by this alleged modification of the intervenient.

Any modification of the air substance would necessarily be corporeal: there must be such an impression as is made upon sealing wax. But this would require that each part of the object of vision be impressed on some corresponding portion of the intervenient: the intervenient, however, in actual contact with the eye would be just that portion whose dimensions the pupil is capable of receiving. But as a matter of fact the entire object appears before the pupil; and it is seen entire by all within that air space for a great extent, in front, sideways, close at hand, from the back, as long as the line of vision is not blocked. This shows that any given portion of the air contains the object of vision, in face view so to speak, and, at once, we are confronted by no merely corporeal phenomena; the facts are explicable only as depending upon the greater laws, the spiritual, of a living being one and self-sensitive.