In James Baldwin's introduction to his 1955 Notes of a Native Son, he references his contemporary Doris Lessing who beautifully stated that prejudice does not come from deeply ingrained sin, it stems from "atrophy of imagination" that "prevents us from seeing ourselves in every creature that breathes under the sun.   Baldwin's wrote about this lack of imagination and societies' multiple realities his entire life. When you fail to imagine another's pain or suffering, you become indifferent and eventually ignorant (although Baldwin called it "innocent") and more capable of "othering another," (to borrow from the precise, almost harmonic words of Toni Morrison.)   
American Jazz singer Billie Holiday describes these multiple realities rather poignantly in her memoirs:   
"Sure, some of them patronized the after-hours joints...but these were just side shows. These places weren’t for real. The life we lived was. But it was all backstage, and damn few white folks ever got to see it. When they did, they might as well have dropped in from another planet. Everything about it seemed to be news to them."

"Our failure is one of imagination, of empathy, if we have failed to hold this reality in mind" agrees Susan Sontag (January 16, 1933 – December 28, 2004), a woman who held our morality in high regard and approached it as one does a beloved old baseball glove: beat it up to keep the fibers supple.

In Regarding the Pain of Others, Sontag deals with the limits of empathy and imagination, particularly as they pertain to visual imagery.

Do photographs make something more real and therefore imperative? Or are we so saturated with images it neutralizes their power?

Holland House, a Jacobean house built in 1602 with later additions by the famous architect Inigo Jones, was almost destroyed in WWII and has never been fully rebuilt. Photograph by Ellen Vrana.

Sontag proposed in her 1979 essay On Photography that "our capacity to respond to our experiences with emotional freshness and ethical pertinence is being sapped by relentless diffusion."

For a long time some people believed that if the horror could be made vivid enough, most people would finally take in the outrageousness, the insanity of war.

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Awareness of the suffering that accumulates in a select number of wars happening elsewhere is something constructed. Principally in the form that is registered by cameras, it flares up, is shared by many people, and fades from view.

In Regarding, however, Sontag concludes that photographs have an effect in that they deliver a "reality that exists independent of the attempts to weaken its authority." We know the Twin Towers fell in 2001 because we saw it in photographs, despite us being far away and despite it being undeniably unfathomable.

As our reality shifts to make room for visual data outside our immediate lives, what are the limits of empathy? What is our capacity for caring? How do we achieve kindness?

Sontag argues that kindness and care are closely tied to pity.   "Pity" is the same word that Wilfred Owen used to describe his poetry written during World War I. "My subject is War, and the pity of War. The Poetry is in the pity." Owen mourned famously. With these words he was to write poetry that "honoured the language of Keats" as well as made very real the reality of war and the spiritual horror of not noticing or caring about death.

 Holland House is also famous because of a 1940 photo. It shows British men in the bombed rubble of the library. They peruse books as if they survived the bombing, a testament to the British spirit of intellectualism and persistence. Except, of course, they visited the site much later and were likely posing for the photographer. The image contained power and falsehood.

It is an issue of caring, but an issue of memory. How do we know, remember, what once happened? How do you jump from a localized occurrence to a collective memory?

And how do you jump from a collective individual memory to a collective societal memory carried through time?

All memory is individual, unreproducible—it dies with each person. What is called collective memory is not remembering but a stipulating: that this is important, and this is the story of how it happened, with the pictures that lock the stories in our minds.

Photographs and images are, like people, witnesses. Those who document for our benefit and speak for our ears. For those who carry this burden of witness know all too well they cannot affect how we feel. It falls on us to look, seek, and learn.

Memorial to the Murdered Jews of Europe, Berlin. We might understand what it means today, we have memories of those who have memories of the Holocaust. But what about in 100 years?

Visual imagery is still monumentally important. I use the word "monument" deliberately. I remember going to the Holocaust Memorial in Boston when it opened. You walk single file through pillars and over grated lights, and the experience is supposed to remind you of gas chambers. Of course, they can't remind us of anything because we have no memory of it. They invoke in us a feeling of terror that kickstarts our empathy. Hopefully. But will it have power in fifty years? One hundred?   Many people have written about how to arrive at meaning and empathy in the face of others' pain and suffering. Christie Watson found the necessary empathy to deliver daily care to her patients by working with a core group of people who felt similarly. For Watson, connectivity delivered fortitude. Read more in The Language of Kindness.

Ultimately, the limits of feeling are just that: feeling. Feeling is not knowledge.   Three compelling contradictions to this suggested limitation of feeling come from environmentalist Rachel Carson, who wrote a wonderful, wonderful book called The Sense of Wonder about how we take in knowledge of the world using our senses and feelings.   
Additionally, read The Accidental Universe from physicist Alan Lightman, who grapples with our position in the uncertain universe and posits “Science is not the only avenue to arrive at knowledge.”   
And, most famously, Daniel Goleman's 1995 book Emotional Intelligence, which coined the eponymous phrase and gives us a brilliant argument for valuing the significance of feelings. As Sontag reminds us, the dead don't care about the living, and the living will never understand the dead, and this impasse, breachable by death or near death, just is. We don't exist after we die.

Sontag closes Regarding the Pain of Others with these lines:

We don't get it. We truly cannot imagine what it was like. We can't imagine how dreadful, how terrifying war is; and how normal it becomes. Can't understand, can't imagine. That's what every soldier, and every journalist and aid worker and independent observer who has put in time under fire and had the luck to elude the death that struck down others nearby, stubbornly feels. And they are right.

Is there any way to avoid reenacting atrocities without knowledge?

Memorial to the Murdered Jews of Europe, Berlin. Memorials must act as both knowledge and emotional loadstones. This Memorial has been criticized for being too abstract, that it fails to deliver knowledge necessary to engender collective memory.

Read Sontag's illuminating essay alongside James Geary's study of language, which invites us to see anew metaphor and its effect on knowledge and meaning, Sontag's own look at the limits of language, Sebastian Junger's study of tribal sentiment as a means of civic trust and engagement for returning soldiers of war, and my own compilation of systematic and figurative ways society falls apart.

When reading Sontag, I cannot help but think of Eli Wiesel's Night in which he wrote "Ours is not to know but to understand." We will never know first-hand what others suffer, or even what they rejoice in. But in connecting to our imagination, to our emotions we can begin to understand.

Understanding is the key to memory, it is the key to caring.