The primary cause of the ship's damage is an iceberg, which the poet describes as
A Shape of Ice, for the time fat and dissociate
However, in the poet's mind, the convergence of the ice and the ship was not an accident:
The Immanent Will that stirs and urges everything
Prepared a sinister mate
For her -- so gaily great --
A Shape of Ice, for the time fat and dissociate.
"The Immanent Will" (God or some other higher power) set in motion the actions that would lead the ship and the iceberg together. The Titanic was the greatest ship that had ever been built. Its makers and owners were full of pride in it and its potential. They believed it was unsinkable, invincible. But "the Spinner of the Years" proved them wrong and
Said "Now!" And each one hears,
And consummation comes, and jars two hemispheres.
So you might say that it was human pride that caused the Titanic to sink.
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