Sentence:  That after <WSD>all</WSD> his years of effort to become a composer , he should now , now when he was still stoutly replying to the critics of his Discourse on the Arts and Sciences , be so close to a success in music and have to reject it . 
Meaning of the word marked with <WSD> tags:  quantifier; used with either mass or count nouns to indicate the whole number or amount of or every one of a class