Once again we find "reality...such as it was" to be a questionable concept that gains meaning only through "belief." In these lines Decoud is fiercely struggling between skepticism and the influence of Antonia's idealism. Though the surface references are to Ribierist politics, "Antonia's belief in the cause" is a loaded phrase that can refer broadly to idealism as such. Likewise, "its crudeness" can refer to that belief. The skeptic Decoud sees the dream-ideal for what it is -- a crude illusion covering a "farce" -- but is helpless before its power to bring the world emotionally "closer."

Note that the narrative evaluation of Decoud has shifted from his introduction in Chapter 2-3. There, his skepticism was called a "pose," while his feelings for Antonia were "genuine impulses." Here, his skepticism is treated as a primary, while his feelings for Antonia are an "infatuation."

The line "he was not a patriot, but a lover" is complex. It means that he intends to love Antonia without caring about her particular cause (Ribierism). In other words, he wants to surrender to pure idealism as such, without surrendering to any particular idealistic credo. Later he will call it "the supreme illusion of a lover."