Ok, I admit it, I've been reading Barthes. So I see semiotics everywhere now. It's all signs! Aiiig! Barthes strikes me as obscure, but not very difficult. He seems to have been a frustrated mathematician, although he may not have known it. He's constantly trying to systematize everything along distinctly mathematical lines with, uh, mixed results, let's say.
Anyways. Be that as it may, I'm not talking about Barthes here. Let's talk about biosemiotics instead, which is a very fancy word for a not very fancy idea. A quick consult on wikipedia will give you the basic idea.
The example always started with is a tick. Its sensorium reduces the world to quite a small set of data: a vague sensitivity to light, a acute sense of smell that works on one chemical associated with mammals, temperature, and hairiness. This suffices to the drive the pattern of the tick's life. The world is modeled in the tick as nothing more than "how light, smelly, warm, and hairy is it here." This world-view is termed umwelt and that's the idea that matters to me.
Light is reduced in the tick to a cascade of biochemical reactions that end up with a specific set of motions, a behavior.
People also have a sensorium which reduces the world. Our vision yields color, but reduced from an infinity of dimentions, to three: R, G, B. Our hearing produces a precise but often inaccurate idea of a sound's origin. Our sense of touch is very relative, and so on. Light, heat, sound, real things are reduced again to cascades of chemical reactions, to neural firing, to cognition (whatever that even is) which all results in behaviors, or doesn't.
Being conscious, or something, we are aware that we live within a model, an umwelt, which isn't the same as reality. Even setting aside dense philosophies that wonder if reality even exists, perhaps the universe is a construct of our conscious observation, Heisenberg! Heisenberg! we still get a separation between our grasp of reality, and reality itself. They're different. We are even clever enough to devise experiments and equipment to probe the underlying reality that our sensorium gives us a précis of.
So all this crap falls under the head of "biosemiotics" and I think the semiotics comes in thus: the "signifier" is the internal model of how bright the light is, the "signified" is the actual light, and the "sign" is the combination of these two. The meaning assigned to the world by the system we name "a tick."
A lot of Arnheim's book Art and Visual Perception is about experiments looking in to what are arguably human biosemiotics, specifically applied to visual representations of stuff.
The evidence of children's drawings suggests that when we see a bus, we identify it as "a horizontal longness" atop "several roundnesses" for instance. Older children draw a box on top of wheels, and later add more boxes for windows.
At some point it leaks over in to cultural semiotics. The meaning of the bus becomes "mode of transportation, primarily for the poor."
I speculate, and this is just me here, that the cultural semiotics and the biological semiotics constitute a spectrum that influences both up and down the chain. We might biologically identify a bus as "moving stone, weird predator" as well as "box on roundness" which flows upwards through langauge and culture to mean "bus." The biological meaning is, naturally, non-verbal so "weird predator" should be understood that way.
The cultural identification of "bus" with "mode of transport for poors" flows downward to soothe the animal and assure it that it's not a weird predator at all, although perhaps best not to stand in front of it.
Let me hasten to add that I don't think these ideas are my invention, they seem pretty obvious so I assume someone else has made similar guesses. I just don't know who, and I don't recall having read them anyplace.
So, traditional semiotics teaches us that we have a word "bus" (signifier) which refers to a specific kind of box on wheels, a real world object (signified) and together these make a sign, and that's what "meaning" is about. Is the signified the actual object, or is it the abstract object our sensorium has identified?
Does the word "bus" point to the actual object, or to the biosemiotic sign for that object? Beats me, not sure it matters much. Angels on pinheads and so on, maybe.
Where I am headed is here: consider a painting of a bus, as compared with a photograph of a bus.
Both will strike us as flat objects with color and tone smeared on them. Both will, eventually, lead the way to the word "bus" and also that internal model of "bus" to which, perhaps, the word refers. That internal model of a bus, that précis of bus-ness that our sensorium digs up when we actually see a real bus, is the landing spot for both the painting and the photograph.
The paths here are many. We go through the word to the précis-model. We go directly to the précis-model and then back to the word. We return to the painting/photo and around and around. There are probably layers of signs and meaning that slosh around.
The part that really matters to me is that I am pretty sure that the photo lights up pathways that are pretty similar to the pathways that a real bus lights up, more than a painting does.
That is to say, a photograph of a bus strikes us the same way a bus does, whereas a painting of a bus strikes us inevitably as a painting of a bus.
My conceit here is that the painting reaches downward, through the cultural and social machinery, through the conscious mind perhaps, to reach the précis-model that carries bus-ness, while the photograph reaches upwards through the biological machinery, the unconscious mind, to reach the same place.
My efforts to devise some sort of cognitive experiment to test this largely failed, except that I returned to the same place I have been before.
Namely, that photographs of great heights induce vertigo, and that pornographic photographs arouse.
In truth, there are probably matters of degree here. Any visual representation will strike us at all levels of semiotics, to one degree or another. A crude sketch of a bus probably does not tickle the biological "moving stone/weird predator" level much at all, but as the depiction of the bus gets more and more realistic, that biosemiotic plane of meaning is more and more activated.
Conversely, one can readily imagine a painting of a bus which activates the cultural semiotic meaning of "transport for poor people" or, better yet, "transport for black people" first and foremost, and has to take quite a journey through our mind to arrive anywhere near the "moving stone/weird predator" plane of meaning.
Anyways, that's my thoughts. Long-time (and especially patient) readers will notice that this is the same sack of shit I've been plugging for like a year now, but dressed up in fancier clothes so I can say "semiotics" over and over, and will sound, um, accordingly smart.