‘Savage indignation there/ Cannot lacerate his breast’ refers to the fact that nothing can hurt him now. The phrase ‘savage indignation’ is very powerful and speaks of the outrage Swift felt, in a very deep sense, at the injustices in the world. ‘Lacerate’ is a potent word, and accurate in describing how Swift was wounded by the injustices he witnessed.
‘Imitate him if you dare’ both encourages us to be like Swift, while warning us that it takes a great amount of courage to be the one to always speak out, no matter what the personal cost. Imagine the bravery it would have taken to have published A Modest Proposal. It was a calculated risk, but it could have gone horribly wrong.
Yeats describes Swift as a ‘World-besotted traveller’, and this eloquently describes what Swift really loved and valued: the world, life and people. The noun ‘traveller’ is both a literal reference to Swift’s love of travel and a reference to the fact that in his life he never stood still or grew complacent, but ‘travelled’ in every sense; mentally, emotionally and spiritually.
The final line of the poem, ‘he/ served human liberty’, is poignant in its simplicity. By looking after the most vulnerable in society and vigorously championing human freedom (at least in Yeats’ opinion), Swift did indeed serve human liberty and made the world a freer and fairer place.