Truth and Photographs

A really interesting essay on truth and photographs:

In discussing truth and photography, we are asking whether a caption or a belief -- whether a statement about a photograph -- is true or false about (the things depicted in) the photograph. A caption is like a statement. It trumpets the claim, "This is the Lusitania." And when we wonder "Is this a photograph of the Lusitania?" we are wondering whether the claim is true or false. The issue of the truth or falsity of a photograph is only meaningful with respect to statements about the photograph. Truth or falsity "adheres" not to the photograph itself but to the statements we make about a photograph. Depending on the statements, our answers change. All alone -- shorn of context, without captions -- a photograph is neither true nor false.

Posted on July 24, 2007 at 1:52 PM • 50 Comments

Comments

AnonymousJuly 24, 2007 2:48 PM

Some photographs are false -- e.g. http://blog.wired.com/wiredphotos54/2007/07/...

It is possible to call a photograph true or false on the basis of whether it misrepresents the reality in front of the lens. That's a valid approach and does not depend on the context or caption.

Of course there is no bright line dividing "true" from "false" here and nature photographers, for example, can argue forever about what constitutes a "manipulated" photo as opposed to a "true" one, but still at the extremes the case is quite clear-cut.

Kaa


Kaa

Knowler LongcloakJuly 24, 2007 3:19 PM

@Kaa

Again it is a statement about the photograph that is true or false. The statement you bring up is "This photo is an accurate representation of what was there."

The photograph itself is neither true or false.

Juha HaatajaJuly 24, 2007 3:23 PM

A nice comment on photographs, but a bit limited one nevertheless.

When talking about digital photographs, we should also take into account the image manipulation done, even within the camera itself. What kind of color balance settings are in use, what kind of sensitivity, smoothing etc.

In fact, the selected combination of these settings may produce a photo which you can say mis-represents the "reality" - that is, the light arriving at the lens - to a significant degree.

Of course, the human eye (and the processing done in the brain) also often mis-represents the "reality" to a significant degree. (The so-called optical illusions are simple examples of this.)

Photographs can represent "reality" and thus provide insight about the world. However, the watcher and reader should beware.

ForRealJuly 24, 2007 3:29 PM

Interesting, given that the Lusitania was the WTC of it's day - to an extent. It was a semi-staged incident used to bring the US to war by an insane president.
To be truthful about the Lusitania it must be said that 1) the German embassy openly, clearly, and more than once announced that the ship was subject to attack. Because 2) The cargo holds of the ship were full of munitions; it was a more than legitimate target of attack. (Were munitions not carried, the attack surely would have been less deadly.)
The Times was a sloppy propaganda outlet back then, and it still is today.

Fred F.July 24, 2007 4:26 PM

Well, to expand that little bit, even without getting into Photoshop or Dodge and Burn (one is digital the other analog). There are many things the photographer can do to change a picture. For example the use of different zooms can make things look different. It was used to nice effect in a current border dispute between Uruguay and Argentina. Uruguay is building an industrial complex and the Argentinians are complaining of visual pollution (among other types of pollution). As proof, a picture was shown of a riverine beach where the smoke stacks of the factory look close and looming. However, that is NOT what a person would see with his/her naked eyes. It was all the result of a choice in a telephoto lens. So was that a fake or not?

Then one can look at composition, etc. That is where the real photographers make money.

AnonymousJuly 24, 2007 4:36 PM

>> All alone -- shorn of context, without captions -- a photograph is neither true nor false.

All alone -- shorn of context, without captions -- a thousand words are neither true nor false.

-S. Photographer

TimJuly 24, 2007 4:59 PM

@ Juha Haataja

On the quantum mechanical level, an observed object changes as a result of it being observed. This is meant literally not just that it changes in the obervers mind. I wonder how this applies to photographs and if observing a photograph can actually have an effect on the object that was photographed. It certainly holds true of people. Think of Marilyn Monroe who would not have been the same person but for her photographic depictions.

@ Fred F.

In Australia the manipulation of real estate photos for the purpose of selling a property is illegal. This is an interesting concept because it would be impossible to prove that a photo (any photo) had not been manipulated. I guess it is the intention of willful misrepresentation that is at issue here.

---------

Does someone know if there is such a thing as a camera that embedds the location and orientation of a photo (as well as all the photographic parameters like exposure, flash, zoom-factor etc.) within the digital photo, then digitally signs it with a time stamp?

billswiftJuly 24, 2007 5:07 PM

A photograph is a statement.
All statements are true or false or undecidable.
If there is not enough context **within** the photograph, it is undecidable without captioning or other explanatory statements or claims.

Filias CupioJuly 24, 2007 5:18 PM

Is the author's audience really so ignorant of history to not know the significance of the Lusitania? I'm neither a historian nor an American, yet I still knew the basics: ocean liner torpedoed by Germans in WW I, people got upset about it.

art IIJuly 24, 2007 6:26 PM

Bruce,

The article was interesting in a way but I suspect that the "Liar, Liar, Pants on Fire" title was partly the reason that you chose it for your blog due to your security background.

The point I'm trying to put across is that a photograph can be an artistic endeavour with no (intended) underlying assertion about truth versus falsehood.

A policeman might use a photograph to break a liar's story. A political propaganda distributor might use a photograph to wip up support for a cause.

Sometimes, however, photography is simply art and it isn't intended to be interpreted in a way that requires judgement.

BLPJuly 24, 2007 7:42 PM

@Tim:

Most DSLRs will record everything the camera can know about the photo, including linking to GPS if the camera supports it -- and the new Canon 1D Mark III will digitally sign raw images so you have an authenticated "negative" to go back to.

The GPS data & lens data & digital signature could, of course, be faked pretty easily. Particularly if you generate a slide, then copy said slide with the camera under "believable" conditions.

David ConradJuly 24, 2007 8:14 PM

Bruce: I get a javascript error every time I access the comments page of any of your blog posts. "commenter_name" not defined. Maybe try "if (typeof(commenter_name) !== "undefined" && commenter_name)"

Also, you might be interested in this story about Fox News leaving a script containing an FTP password in a readable directory on their web server:

http://linuxinit.net/site/?id=664

cookseyJuly 24, 2007 8:22 PM

We have reached a point where "reality" as depicted in a printed image is fairly plastic and malleable.

This is on a level where the changes are undetectable in web or print resolutions. If the imagemaker is willing to spend the time they can create many untrue realities.

This may be relatively benign like thickening up the bushes on a house or fixing a persons hair. It gets worse from there especially with images thar are supposed to be “photographs��? rather then manipulated “photo-illustrations��?

The case of the Lebanese city on fire was a gross example. I recognized the clone brush artifacts in the smoke immediately and was shocked at the time that they would let that go public.

I was not surprised to see it be corrected shortly thereafter…

Still…

All this is supra-liminal manipulation. If you observe a hi-res version of the file and know what to look for you will be able to tweeze out the changes. So as with all supra-liminal suggestive elements there is still a level of inherent disbelief that needs to be overcome.

There is a lot more sublime manipulation that takes place where camera angle, lighting, subject placement and focus play into making a compelling image with good hidden persuaders.

An experienced imagemaker manipulates these elements in real time to get a good shot from any given situation. The editor manipulates after the fact by selection of images from a body of work.

These are the things that I think can really alter your perception of the “truth��? of a picture. It is the stuff that you don’t see in an image that will give you a feeling of right-ness.

In the end a picture is generally untrue in some way because that is the nature of an artists vision and their visual parsing of reality.

Digital has enabled the gross manipulation of images but the old standard ways of playing the observer, camera angle, lighting, blocking and focus are the things that most strongly contribute to making people feel one way or another about the truthfulness of an image…

Terry ClothJuly 24, 2007 8:25 PM

Back in the day, a photograph was fairly easy to introduce into evidence at a trial. Today, the only rational way to do it is to put the photographer on the witness stand and swear that the photograph is unaltered. Any other procedure means the photo is meaningless.

Of course, there's always perjury....

antibozoJuly 24, 2007 9:30 PM

Knowler Longcloak> Again it is a statement about the photograph that is true or false. The statement you bring up is "This photo is an accurate representation of what was there."

Knowler Longcloak> The photograph itself is neither true or false.

Uh, no.

Truth is generally the degree to which a model resembles the thing modeled. The metric by which we measure truth varies with context. A "true" statement is an accurate semantic model of its subject (which may be real or metaphysical). A "true" wheel accurately models an idealized wheel geometrically. A "true" photograph might be one in which parallel lines on the subject are rendered in parallel on the photograph, one that accurately reproduces color for the human eye, one that accurately reproduces tone for the human eye, or any number of other things, depending on the properties of the model that are sought after for the purpose of the photograph--the chosen metric. All of that is independent of anything written nearby; information is not conveyed solely by captions, after all.

Ceci n'est pas une pipe. Everything is a model, including this.

gregJuly 25, 2007 1:55 AM

@BLP

Not to mention DSLR have a proper dynamic range and decent lens (size etc). I just don't take enough "proper" photos to justify one. But they are cool.

Just a question. What signing do they do? Is it just a hash or something more public key like..

someoneJuly 25, 2007 3:20 AM

a friend of mine differentiates between images and photos. a photo is not allowed to be modified, an image is.
i think this should be introduced in web and print

AnonymousJuly 25, 2007 3:21 AM

a friend of mine differentiates between images and photos. a photo is not allowed to be modified, an image is.
i think this language should be introduced in web and print.

antibozoJuly 25, 2007 3:36 AM

someone> a friend of mine differentiates between images and photos. a photo is not allowed to be modified, an image is.
someone> i think this language should be introduced in web and print.

There is already an established distinction: a photo is an image that is produced by a photographic process, i.e. a process where electromagnetic radiation from the subject is projected through a lens onto a recording surface, generating a chemical or electrical image of the subject.

bakoJuly 25, 2007 8:50 AM

The point is, there is *never* enough context within the photograph. And "reality" has nothing to do with "true" or "false". If you're expecting reality from a photo, you're giving it context and expectation that the photo alone does not provide.

Take the famous picture of the tourist on top of the WTC with the plane in the background. Is it true or false? If the claim is it's a real photo, it's false; if the claim is that it's a joke picture or even a piece propaganda to get a rise out of people, then it's true. But without one of those statements, or some other statement about it, the photo itself cannot be true or false.

bakoJuly 25, 2007 8:57 AM

@someone,

I see the point of the distinction, but how do you define an unmodified photo? You can take a hundred photos of the exact same thing with a hundred cameras and get a hundred photos that all look very different from each other, and none of them may reflect what the photographers saw with their naked eyes. The type of film, the method of developing, the aperture used, all manipulate the photo from the get-go.

Consider that the world wasn't black and white or sepia before we had color film; does that mean every photo from that time is false?

bakoJuly 25, 2007 9:32 AM

antibozo> "A "true" photograph might be one in which parallel lines on the subject are rendered in parallel on the photograph, one that accurately reproduces color for the human eye, one that accurately reproduces tone for the human eye, or any number of other things, depending on the properties of the model that are sought after for the purpose of the photograph--the chosen metric.'


In other words, a "true photograph" is one that meets the chosen definition of "true photograph". Which is the point of the article and the bit you quoted from Longcloak. You have to say what "true photograph" is before a photograph can be called true; there's no such thing as an objectively true photograph.

billswiftJuly 25, 2007 9:43 AM

> Back in the day, a photograph was fairly easy to introduce into evidence at a trial. Today, the only rational way to do it is to put the photographer on the witness stand and swear that the photograph is unaltered. Any other procedure means the photo is meaningless.

>Of course, there's always perjury....

Technological recordings of all types are fairly straightforward to manipulate; all they are good for is to provide specifics that a person can testify to.

On a related note, remember the fuss about Linda Tripp recording her discussions with Lewinsky? I thought at the time, and even more strongly now, that laws against one party's to a conversation, or other interaction, are proof of the essentially criminal nature of government - the person can still testify, formally or otherwise, as to what was said, all a recording is good for is exposing who is lying. So laws against recording by one party, and photography or videotaping of envcounters, only benefits liars and crooks.

antibozoJuly 25, 2007 12:03 PM

bako> In other words, a "true photograph" is one that meets the chosen definition of "true photograph". Which is the point of the article and the bit you quoted from Longcloak. You have to say what "true photograph" is before a photograph can be called true; there's no such thing as an objectively true photograph.

Yes, and there is no such thing as an objectively true *anything*. Assessing truth always requires assigning context. "Two plus two equal four" is only true if you assume we're using modern English, you agree what "two", "plus", "equal", and "four" mean, you agree that the glyphs used in the statement correspond to the letters of the English alphabet, and that the orthography used in the statement indicates that t-w-o spells the word "two", and so on. Without assuming a vast amount of context, any printed statement is just an image of a bunch of squiggly lines. Try this for example: write "two plus two equal four" as iso-8859-1 character values in hexadecimal--now is that string "true"?

bakoJuly 25, 2007 12:50 PM

@bako,
So we're all in agreement. You need context for a photo to be labelled true or false.

antibozoJuly 25, 2007 1:00 PM

bako> So we're all in agreement. You need context for a photo to be labelled true or false.

I don't think we agree at all. As I said, you need context for anything to be labeled true of false. There is no distinction between a photo and a statement in a given language as to its objective truth--to assess truth of any representation of information, you always need to decide what the representation is modeling.

One might argue, in fact, that truth of a photo is easier to assess objectively than that of a statement. If a sighted extraterrestrial visits Yosemite holding a calendar with an Ansel Adams photograph of Half Dome, it is going to be able to say the photograph is true by a number of measures, while completely unable to assess the truth of the photo's caption without doing considerable research into human language, the history of names of North American features (not everyone has called it "Half Dome"), the history of photography (to determine whether use of the name "Half Dome" is synchronic with the representation), Ansel Adams, etc.

bakoJuly 25, 2007 1:13 PM

@antibozo,
I think we agree on the objectivity of truth re a photo. If we don't, I"m not sure where.

As to the Half Dome photo, by what measures could it be called "true"? Adams' photo is black-and-white -- that alone does not reflect reality. We are not seeing what Adams saw as he stood before the Dome. The calendar is obviously not the original photo -- it may not be a photo of the Half Dome but a photo of a photo. Couldn't it be argued that that makes it untrue? Maybe it's a photo of a very good model of the dome. True or no?

antibozoJuly 25, 2007 1:56 PM

bako> I think we agree on the objectivity of truth re a photo. If we don't, I"m not sure where.

Perhaps we agree on that, but citing that alone as you did above seems dismissive of our apparent differences.

bako> As to the Half Dome photo, by what measures could it be called "true"?

1. By a monotonic mapping between the energy of reflected light from Half Dome at specific wavelengths and the tone represented in the photograph, for an observer situated somewhere near where Adams set up his view camera.

2. By a spatial mapping between the morphology of a projection of Half Dome through an idealized lens onto a planar surface and the morphology of the photograph.

3. Adding some context about Adams's particular processes, by the manner in which the photograph models his strategy for mapping measured light energy into printed tone values.

4. Adding some historical and psychological context, by the manner in which the relative effort, care, and quality of the processes Adams used to photograph and print the image of Half Dome reflect a human reverence for the processes which produced Half Dome itself, and for the effect of its sight on the human mind.

One can continue evaluating the photograph with increasing knowledge of its context to understand additional truth. To get to the point of understanding the truth of its caption, however, the extraterrestrial must do a huge amount of work, while some truth is readily evident given the photograph alone.

For comparison, consider this scenario. In a cave in Yosemite, someone discovers what appears to be a prehistoric painting of Half Dome, but with the English words "Half Dome" inscribed using the same process beneath it. We show this representation to the extraterrestrial. How much context will the extraterrestrial need to understand that there is something false about this representation, even though the painting itself represents the morphology of Half Dome accurately?

bako> Maybe it's a photo of a very good model of the dome. True or no?

True if by the chosen metrics it is evaluated thus. A scale model of the Titanic may be very true in terms of linear proportions, while false in terms of the material it is made out of, its location somewhere other than the bottom of the North Atlantic ocean, the intactness of its hull, the function of its propulsion system, etc.

bakoJuly 25, 2007 2:23 PM

All those methods would let one determine whether the photo is an untainted image from life. They don't tell me whether it's true, unless I consider a true photo to be one that is an untainted image from life.

"This is written in German." is a true sentence, in the sense that it meets all agreed upon criteria for an English sentence. It is not a true sentence in that interpreting it will reveal truth.

I guess I'm not addressing the point about a photo needing less context than text. I agree with that, at least as far as the examples go. If the photo was instead, say, Tom Hanks shaking hands with JFK, the exercise changes completely.

bakoJuly 25, 2007 2:23 PM

All those methods would let one determine whether the photo is an untainted image from life. They don't tell me whether it's true, unless I consider a true photo to be one that is an untainted image from life.

"This is written in German." is a true sentence, in the sense that it meets all agreed upon criteria for an English sentence. It is not a true sentence in the sense that interpreting it will reveal truth.

I guess I'm not addressing the point about a photo needing less context than text. I agree with that, at least as far as the examples go. If the photo was instead, say, Tom Hanks shaking hands with JFK, the exercise changes completely.

AnonymousJuly 25, 2007 5:12 PM

bako> All those methods would let one determine whether the photo is an untainted image from life. They don't tell me whether it's true, unless I consider a true photo to be one that is an untainted image from life.

I'll repeat something I said earlier:

Truth is generally the degree to which a model resembles the thing modeled.

A statement in a natural human language is a model of an idea in someone's head. The idea is a model of something else. There is a measure of truth in how well the statement semantically models the idea using the presumptions of language for the writer and reader, and another measure of truth in how well the idea the statement represents models something else. "John went to the store" may be a true model of something I believe, which may be true of reality if in reality the "John" I'm thinking of went to the "store" I'm thinking of.

Years ago I worked in a studio printing color photographs of works of art. There is an expectation of truth between the photographer, printer, and artist that the final photograph will as closely represent the original work as possible. Most colors in a photograph will be perceptibly wrong to some degree; there's a great deal of interpretation and judgment to be made by the printer in choosing a color balance and density that will be satisfactory to the artist, and making these choices may involve asking the artist which colors he or she deems most important to the piece. But none of that needs to involve the meaning of the artwork, or even its title.

There is no inherent truth in any particular model--statement, photograph, audio recording, mathematical formula, etc. Truth is a property of the relationship between a model and its referent, and possibly that referent's referent, and so on.

bakoJuly 25, 2007 6:23 PM

I continue to be confused at what you think the difference is. I originally quoted you because you negated someone else when they said that a photo in itself cannot be true or false. But in all your arguments, there is some "thing modeled" that must be adequately matched for the photo to be considered true. So without some thing-to-be-modeled, there can be no truth in a photo, or in anything. Yes?

antibozoJuly 26, 2007 3:48 AM

bako> I originally quoted you because you negated someone else when they said that a photo in itself cannot be true or false.

What I disagreed with is the notion that a photo by itself has any more or less inherent truth than any other representation of information.

The essay, while moderately interesting (mostly because of the small history lesson it contains), is facile and fallacious. Here's the argument in a nutshell:

1. The author writes: "Look at the photograph below. Is it true or false?" and shows us a captionless image of a ship. Then he comments, "I find the question [is it true or false] ridiculous: 'True or false in regard to what?'"

Indeed, the question is ridiculous, as we haven't been given a metric by which to measure truth. That's the author's fault, though.

Some readers--maritime and war historians, for example--will recognize the ship without a caption. These people will say, "That looks like a pretty good photograph of the Lusitania." For these people, the photograph is already true, in that it accurately represents what the Lusitania looked like. For the rest of us, the photograph is still "true" if it is an image of some ship, even though we might not know what ship it is. The image is also somewhat false in that the highlights and shadows don't accurately represent the reality that was photographed. But even without knowing what ship it was, we may still assess the truth of the photograph on a number of levels.

2. The author shows us the photograph again, this time captioned "The Lusitania", and asserts that "Only now can we ask questions that have true or false answers."

This is simply wrong. The caption doesn't change the truth of the photograph. What the caption does is name a referent, and now we may assess, after some research, whether the referent named by the caption is in fact the photograph's referent, and thus whether the *caption* is true. Obviously, before we had the caption, we couldn't assess the truth of the caption, so the author has actually demonstrated nothing at all.

3. The author tells us a little about WWI and the context of the Lusitania. Then he shows us the image once more and claims that "the image remains the same, but clearly we look at the image in a different way."

This is all completely unrelated to the truth of the photograph. It's just more warm fuzzy writing to distract the critical mind. And of course the WWI historians already knew all that and aren't looking at the image "in a different way" at all.

4. Finally, the author claims that "photographs are neither true nor false in and of themselves. They are only true or false with respect to statements that we make about them or the questions that we might ask of them."

This conclusion is not supported by the essay. Ironically, the author apparently hasn't even thought much about what "truth" or "meaning" are.

Photographs are models. The truth of any model is its success at recording certain desired properties of its referent. Obviously if we don't know what the referent is, we can't say how true the model is. I might assert that "A*B = 6", but no one can assess the truth of that statement without knowing more. But the truth of "A*B = 6" is not determined by anyone's knowledge of A and B. It is determined by the semantic values of the various symbols in the formula, and the particular values of A and B. To assess the truth of any model, we always must first know what the model's referent is and what metric of truth we are to apply.

jetJuly 26, 2007 2:10 PM

Bruce,

I can't find my notes from Journalism school a couple of decades ago, but I can try finding the cite if you're interested.

When photography was initially introduced to newspapers, many people objected given how easy it was for any person to lie about the news by taking subjective or posed photographs and have them printed by a newspaper.

On the other hand, a known illustrator (A. Famous Illustrator) could be trusted to visit a scene and accurately represent what he (usually "he") saw in the form of hand-generated drawings. The difficulty in copying the signature style of A. Famous Illustrator was so difficult that making a counterfit/fake drawing by A. Famous Illustrator was nearly impossible for the average person.

Thus, an illustration by A. Famous Illustrator would be perceived as more accurate or "real" than a photograph by an anonymous newspaper photographer.

Obviously this changed over time, but it's an interesting perspective on authorship and trust in the person who creates an image.

X the UnknownJuly 27, 2007 12:07 AM

I think that the statement "Truth or falsity "adheres" not to the photograph itself but to the statements we make about a photograph" is insightful, and is basically a concise way of saying the context in which a photograph (or anything else, really) is presented affects our judgment of veracity.


I would agree that *technically", a picture is neither True nor False. However, particularly with a photograph, it is easy to present an image with *implied context* that, absent a caption, effectively makes the photo a deliberate lie.

A very common example of this would be those pictures of people standing with their arm around some celebrity or another - when the celebrity was really a photorealistic cardboard cutout. Since the photo of me standing with Gretta Garbo (or whomever) is itself two-dimensional, if it was taken from the correct angle it is very difficult to tell that the celebrity isn't "real".

*Absent* caption, this kind of photo clearly asserts that "I met Garbo". It is only with a caption to override the "default context" that it can be made "True" (e.g. "A picture of me with a cutout of Gretta Garbo").

A much-more nefarious use of such a technique would be to make a poor-quality photo of some well-known figure (say, the mayor of Washington DC - those pictures used in his trial were of terrible quality) in morally/ethically/legally suspect circumstances (say, with a prostitute). The subject could easily be just a reasonable look-alike, or the entire picture could be an artistic rendering. If "leaked" to the public with no caption or commentary, some portion of the public will simply "believe the evidence".

Sure, there is actually an implied statement: "This is a true representation of an actual event", that caries the veracity (or lack thereof). But, I maintain that, in many (usually predictable) circumstances, that implied statement *IS* the default context for a realistic-looking image. In that sense, we can definitely say "this image is false", as (absent overriding context) it is intended to deceive.

Similarly, certain optical illusions could be said to be "inherently false" images. They are constructed in such a way as to deliberately abuse the limitations and mechanisms of vision and/or recognition. Of course, we don't generally think of them as True or False, but rather as interesting. But, the fact that a normal person *cannot* accurately see the totality of the image would certainly seem to make it a "false image". Red/Blue color-vibration is a simple example of a physiological limitation that can be exploited to produce a "false image", in that it simply cannot be accurately "seen" by a human being with normal color-vision.

antibozoJuly 28, 2007 6:21 PM

X the Unknown> I think that the statement "Truth or falsity "adheres" not to the photograph itself but to the statements we make about a photograph" is insightful, and is basically a concise way of saying the context in which a photograph (or anything else, really) is presented affects our judgment of veracity.

But isn't it obvious that context influences everything? And "veracity" itself has many layers.

X the Unknown> A very common example of this would be those pictures of people standing with their arm around some celebrity or another - when the celebrity was really a photorealistic cardboard cutout. Since the photo of me standing with Gretta Garbo (or whomever) is itself two-dimensional, if it was taken from the correct angle it is very difficult to tell that the celebrity isn't "real".

But here's what really happens: the photograph is a model of a scene. The viewer sees the image and autonomically builds a spatial model of the scene in his or her head, then compares the spatial model with the image. If the lighting or scale is inconsistent, the viewer may detect this and reanalyze the image (again autonomically) to find a more plausible scene. If there's no cue that the referent scene isn't actually you with Greta Garbo, the viewer *may* assume that you were standing next to Greta Garbo--what you mean by "default context".

But the viewer's assumption, right or wrong, isn't about the truth of the image; it's a result of a complex mental process that factors in context and knowledge. If the image is next to a newspaper article about Greta Garbo, the natural assumption is that the image represents what it appears on the surface--a scene that really happened. If, however, the photograph is on page sixteen of the book "Pictures of Me with Cardboard Cutouts", then the viewer's mentally constructed scene will tend toward the cardboard cutout version--even if the referent scene did *not* use a cardboard cutout. It's not the photograph itself that does this; it's a matter of how the photo's context--caption, juxtaposition with other images, enclosing medium, etc--influences how the viewer imagines the referent scene of the photo, combined with the viewer's knowledge. After all, if you already *know* it's a cardboard cutout, that's the scene you'll build in your mind, no matter what the photo looks like.

It's no different with text, audio, film, or any other medium. The medium itself presents a physical model of some referent. The viewer uses that physical model to build a conceptual model of the referent. That referent may be part of a long chain of reference linked to real, historical, or metaphysical concepts, and the viewer will perform varying consistency checks on many layers in that chain.

X the Unknown> Similarly, certain optical illusions could be said to be "inherently false" images. They are constructed in such a way as to deliberately abuse the limitations and mechanisms of vision and/or recognition. Of course, we don't generally think of them as True or False, but rather as interesting. But, the fact that a normal person *cannot* accurately see the totality of the image would certainly seem to make it a "false image".

Well, consider special effects in film--in fact, consider this scene in particular, from "Postcards from the Edge". We see Meryl Streep hanging from the side of a building, the camera looking down over the edge to see the street below, clearly a fatal fall if she should let go. She cries "Help! Help!" Is the image false? No, the image is an accurate representation of what the camera sees. Is our conceptual model of the scene false? Yes, but we don't know until Meryl's cries become less convincing and she then lifts her hands from the edge of the building, at which point we perceive that she is simply lying horizontally on top of a false building with forced perspective and background painting--filming a movie scene--and we revise our conceptual model of the scene suitably. The camera photographs an image which our minds plausibly reconstruct as a life-threatening situation, reinforced by her cries for help. Before the reveal we may imagine her state of mind, and sympathize with her fear of falling to certain death and feeling of desparation and despair. All of these things are true--these are things people feel in such a situation. After the reveal, we understand different true things--Meryl's character is an actress, her desperation is false or perhaps self-inflicted, she's feeling depressed and uncertain about her career. All of this is, of course, in the context of a movie, so none of the surface referents are real, though we may understand, if we know enough about the film, that the story is from a semi-autobiographical book by Carrie Fisher.

Despite all these layers of reference, what most of us understand theoretically about human behavior and experience from watching this scene is true in many ways. One of those is that our conceptual model of Meryl's character in the scene matches the model the scene's author had in mind.

I could go on, but I've bored everyone to death already.

[X the Unknown--fun film, BTW. ;^) ]

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