The photograph with no caption

The same photograph appeared in two newspapers on the same morning. In one it illustrated a story about a protest; in the other, a story about a festival. The image was of a crowd in a street.

Neither paper had altered the picture. The crowd, the light and the banners were identical. What differed was the sentence underneath, and the sentence did most of the work. Readers of the first paper recalled seeing tension in the faces; readers of the second recalled celebration. When researchers later showed the image without any caption, descriptions clustered around 'a lot of people outdoors'.

This is not a trick peculiar to photography. Any evidence that is ambiguous takes its meaning from the frame placed around it, and photographs are unusually ambiguous because they look unusually direct. A sentence can be challenged; a picture seems to arrive before interpretation, which is precisely why the interpretation attached to it passes unexamined.

Picture editors know this, and the better newsrooms treat captions as factual claims subject to the same checks as the text. A caption that says 'protesters gather' asserts something about intention that the photograph cannot show. If the only evidence for the word 'protesters' is the article it sits beside, the caption is circular.

The practical advice for a reader is awkward but effective: look at the photograph first and describe it to yourself before reading the caption. What survives that description is what the picture actually contains. Everything else was supplied by the words, and the words are an argument rather than a record.