First of all the author states that English language is the richest for poetry, but he immediately makes a qualification of the statement, claiming that this doesn't mean that England has produced the largest number of poets. He also makes a further clarification, that English language is the best for poetical purposes because it has the largest vocabulary.
To outline his theory he starts adding information linked to a supporting statement. In his opinion the English's richness his due to various elements has a Germanic foundation, a Scandinavian element, a Norman French element, French and Latin influences and the Celtic language.
This ideas are clarified with the analysis of the English rhythmic variety richness, linked to the Saxon verse, the Norman French and Welsh rhythm, and also of the Latin and Greek poetry.
Furthermore the main ideas are marked again using restatements involving the reasons why English is such a good language for poetry and that England has not necessary produced the greatest poets.
The author goes on claiming that generally people think that a nation excels in one art, like Italy and France in art, Germany in music and England in poetry. Yet this is seen as not true, as no art has ever been the exclusive possession of only one nation, and also there have been periods in which other countries than England took the lead in poetry, as France in the mid-19th century.
Therefore the author makes a further refutation about this idea, as he asserts that no English poet contemporary to Goethe can be compared with him.
In addition it's stated the idea that no European nation would have achieved what they had if no other country also developed those art forms.

Finally the author, using a statement, explains that European literature ability o renew itself depends on the capability of receive and assimilate influences from abroad and to go back and learn from it's own sources.