Could we explore a bit in how it would cost them money. Taxes in general get back into the economy unless the government stockpile the revenue or invest them over sea. It would increase costs for companies doing exports, raising costs on mining (29.9% of total exports), and maybe organic chemicals exports. Switzerland second largest export is Pharmaceuticals, but I am unsure how much a carbon tax would impact that industry.

If they also applied it to imports then countries with high CO2 would have a harder time to export to Switzerland. Having less access to cheap products with high carbon footprint would add a costs to citizens, as alternative products will likely cost more, but then it would also encourage industries in China/India to produce products with lower footprint in order to compete on markets with carbon taxes/tariffs based on carbon footprint. It might even encourage local productions which can be a boon for the economy.