I read this important paper a little earlier today, and here is my attempt to summarize and clarify some of his ideas. In my head at least.
Habermas defends modernity from postmodernity which according to him presents itself as “Antimodernity”. What does this mean? He defines modernity roughly as distinguished from the past. More accurately perhaps, it would be described as in an opposing or contrary opposition with the past.
The idea of being modern, he writes, originates with a belief we have that the now is somehow different in a significant way to the past. A belief inspired by the progress of modern science and the changes observed in society and culture.
These ideas of modernity, according to Habermas have climaxed with the Dadaist and with Surrealism. Their rebellion and significance however have failed. The so-called avant-garde of today by constantly searching for, and exploring new territories reveals within itself a longing for a stable present. A longing for stability. Ultimately, by failing to keep attempting a distinction between the past and the present, despite the dominance of modernism in our culture, it is dead.
Despite the death of modernism, Habermas thinks that we ought to not give up on the project it has given itself. Instead, we should continue with its task and at the same time learn from the failure of dadaism and surrealism, who while modernist, Habermas sees as trying to in a way negate modernity.
The task of modernity emerges during the enlightenment. It was to develop an objective science, universal morality and law, and an autonomous art. In the 20th century these ideas have split from every day discourse by becoming specialized. Therefore it appears that his solution is to simply bring them back into common discourse.