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Saccard argues, and the novel partly grants, that money-lust and gambling are the manure from which real enterprises grow: without the fever of speculation, no one would fund railways, canals, and Middle Eastern development schemes. The same greed that ruins small investors also mobilizes capital for projects prudent finance would never attempt, so destruction and creation come from one mechanism.
The Banque Universelle secretly buys its own shares through front men and bank-held accounts to push the price ever higher, turning its capital into a stake in its own stock rather than productive assets. Rising paper value then justifies new capital increases, so the institution's apparent strength is only its own buying.
The Jewish banker Gundermann, who has no desires of his own, simply keeps selling short and waits, because he knows a price held up by artificial buying must eventually meet the limit of available cash. Saccard's enthusiasm and vision lose to an opponent whose only weapon is the arithmetic of liquidity and time.
When the Universelle crashes, the insiders and great bankers largely escape while ruin spreads to the modest believers: aristocratic families, clerks, servants, and pensioners who put their life savings into shares out of faith in the promoter. Financial manias recruit the least informed at the peak, so losses concentrate among those furthest from the information.