Look at a stone cutter ...

Look at a stone cutter 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 will split in two, and I know it was not the last blow that did it, but all that had gone before.
 Jacob August Riis

Quotes from the same author

Long ago it was said that 'one half of the world does not know how the other half lives.' That was true then. It did not know because it did not care. The half that was on top cared little for the struggles, and less for the fate, of those who were underneath, so long as it was able to hold them there and keep its own seat.
 Jacob August Riis
The more I live, the more I think that humor is the saving sense.
 Jacob August Riis