Zen Pencils explains:

Jacob A. Riis (1849-1914) was a Danish-American social reformer, journalist and photographer. Immigrating to New York from Denmark when he was 21, he found work as a police reporter covering the Lower East Side. Riis was deeply affected by the terrible conditions people were living in and set about reporting on everything he saw. His pioneering photojournalism work culminated in the book How The Other Half Lives, which for the first time documented the plight of the working class in New York.

Riis’s now-famous ‘stonecutter’ quote is taken from his autobiography The Making of an American. Riis is writing about the huge uphill battle he had trying to improve the conditions of the police lodging dens and tenement slums, which were cesspools of disease and squalor:

“And I know now that I was right. But it takes a lot of telling to make a city know when it is doing wrong. However, that was what I was there for. When it didn’t seem to help, I would go and look at a stonecutter hammering away at his rock perhaps a hundred times without as much as a crack showing in it. Yet at the hundred and first blow it would split in two, and I knew it was not that blow that did it, but all that had gone before together. When my fellow-workers smiled, I used to remind them of the Israelites that marched seven times around Jericho and blew their horns before the walls fell.

“Well, you go ahead and blow yours,” they said; “you have the faith.”And I did, and the walls did fall, though it took nearly twice seven years. But they came down, as the walls of ignorance and indifference must every time, if you blow hard enough and long enough, with faith in your cause and in your fellow-man. It is just a question of endurance. If you keep it up, they can’t.”

You can see a collection of Riis’s photographs here.

Previous comics featuring the boy Dragonslayer: 

Calvin Coolidge. Oswald Chambers. Samuel Beckett. Winston Churchill. Robert Kennedy.

– Riis had help shutting down the police lodging dens from future president Theodore Roosevelt, who was NY police commissioner at the time. The two went on to become lifelong friends.

– The stonecutter quote is the mantra of the NBA team San Antonio Spurs (shout out to Aussie player Patty Mills!). A favourite of coach Gregg Popovich, the quote is stuck on the wall in the Spurs locker room (and is translated into French, Spanish and Portuguese to accommodate the team’s international roster). If that’s not enough, Popovich’s small wine label is called Rock and Hammer and the team’s fan website is named Pounding the Rock.