Every second of every day a camera shutter is clicking, capturing happiness, greed, sorrow, death, sex, childbirth and other expressions of life that cannot adequately be captured in words. People gather facts primarily through their eyes, rather than by hearing words, so it is natural for anything visually striking to stick in the mind.
Because of this, still images are extremely powerful - not a fleet of moving images that can be easily forgotten, but a single frame embedded and standing out from all our memories. The old saying is 'a picture paints a thousand words', but it is actually many, many more. Pictures are the first thing we notice in a publication - and the last thing we forget.
As a reader once observed, the images in newspapers lived on long after he had lit the fire with them.
If we close our eyes and think of the first man on the moon, 9/11, Prince Charles kissing Lady Diana after their wedding, the lone man in front of a tank in Tiananmen Square - or more recently the capture of Saddam Hussein and American hostage Nick Berg being beheaded - it always comes back to a single image in the mind,
not a paragraph of words or a show-reel. Nearly 40 years on, everyone remembers the image of the young girl running naked in Vietnam. Who remembers the headline?
The most controversial photographs over the past month are those of US soldiers abusing prisoners of war and the infamous Daily Mirror fakes - images that supposedly depicted British soldiers torturing captives.
Was the Mirror's former editor Piers Morgan justified in his decision to publish or not? It is likely he gambled that the images, while of unproven provenance, nevertheless served to illustrate a story as true as the other emerging photographs showing American soldiers committing similar and worse acts.
Whatever the motives for publishing - and whether it was right or wrong - Morgan fuelled a new level of debate on whether we should be involved in such a conflict; one in which torture - even if perpetrated solely by our American allies - is part of the story.
The real US images are all the more distressing because they show perpetrators revelling in their deeds, as well as the suffering of the victims. This is unusual in torture scenes; victims, not abusers, are usually the focus - such as in pictures from the Holocaust of the Second World War.
The prisoner pictures also portray scenes of degradation and nudity that break religious taboos and could, as a consequence, have repercussions on the US and UK's relationship with the Arab world for many years.
'Unfortunately, the defining images of the war in Iraq will be pictures of prisoner abuse rather than images of courage and bravery,' says Justin Sutcliffe, a veteran war photographer who has worked in conflict zones including Iraq, Afghanistan and Zimbabwe. 'They will haunt us for generations because they seem to confirm the the Arab world's worst fears of us all.'
Just as photographs have an innate power to cast a shadow over the world, so they can be inspirational and positive. Neil Armstrong on the moon, the conquering of Everest and the collapse of the Berlin Wall are powerful 20th Century symbols of human endeavour and achievement. These all endure in our minds.
Advertisers have always understood and used the power of good images - as have propagandists throughout history. But PROs do not seem to be as aware of the potential of visual communication. More often than not they are word-driven in their focus, relegating pictures to an afterthought in their well-planned campaigns - if they've thought 'pictures' at all.
Or if they do commission photography, they spend more time worrying about client perceptions than trusting photographers' ideas or giving them time to capture the right image.
Harness the power of pictures
PROs need to consider how they can harness the power of pictures without falling into the trap of trying to advertise or market businesses, products and services in a way that turns picture editors off; or, worse still, creating an image that can be used time and again to demonstrate folly. Government minister John Gummer giving his child a hamburger in order to 'prove' BSE was not a big issue, over a decade ago, is a case in point.
When using photography, PROs should think around the subject and not go for the most obvious option. Most importantly it is a humanising element that gives a picture interest. As Evening Standard picture editor Dave Ofield says: 'Ultimately, the picture editor is a gatekeeper whose eye looks out for great reportage, an image that tells a story in an instant.
That's what PR people should be trying to achieve. We see thousands of images a day, but pictures that tell a story stand out from the rest.'
As the multi-layered tragedy of Iraq demonstrates, pictures are powerful enough to cross linguistic and cultural boundaries. They have a universal appeal that transcends all languages, touching the hearts and minds of people across the world. Photographs that do this have the power to win universal acclaim or to cause universal outrage.
As the Prime Minister ponders the options in Iraq and defends the moral reasoning for bringing the UK into the war, a constant flow of images from the conflict will continue to convey things that words alone cannot describe.