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In page Émile Zola:

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In Zola there is the theorist and the writer, the poet, the scientist and the optimist – features that are basically joined in his own confession of positivism;[citation needed] later in his life, when he saw his own position turning into an anachronism, he would still style himself with irony and sadness over the lost cause as "an old and rugged Positivist".[1][2]