Here is the wikipedia story on "Invictus"
Invictus is a short poem by the British poet William Ernest Henley. The title is Latin for "unconquered". It was first published in 1875.
At the age of 12 Henley became a victim of tuberculosis of the bone. In spite of this, in 1867 he successfully passed the Oxford local examination as a senior student. His diseased foot had to be amputated directly below the knee; physicians announced the only way to save his life was to amputate the other. Henley persevered and survived with one foot intact. He was discharged in 1875, and was able to lead an active life for nearly 30 years despite his disability. With an artificial foot, he lived until the age of 54. "Invictus" was written from a hospital bed.
Out of the night that covers me, Black as the Pit from pole to pole, I thank whatever gods may be for my unconquerable soul. In the fell clutch of Circumstance I have not winced nor cried aloud.Under the bludgeonings of Chance my head is bloody, but unbowed. Beyond this place of wrath and tears looms but the Horror of the shade, and yet the menace of the years finds, and shall find me, unafraid. It matters not how strait the gate, how charged with punishments the scroll, I am the master of my fate: I am the captain of my soul.
Art Berg's life was a testament to the message he tried to get all to understand. It is not the circumstances of our life that determine our destiny, it is our response to our circumstances that determine our fate.