From the pension system which is separate from taxation. De jure the current pensioners paid into the system for decades and now get paid back. De facto they get funded by contributions of the currently employed, but they don't swallow up any tax money or hold anyone hostage because if the current system was scrapped there would not be more tax money available for other things (e.g. public transport). The money is collected by a dedicated agency and does not flow through the government.

The current system is hated by people who've been farmongered into thinking there won't be any pensions when it's their turn (this tactic has been around for at least 50 years and hasn't happened yet). And also successfully FOMOed into thinking they are missing out on huge gainz if they would invest the money otherwise. Even though probably true, I quite like the current system of solidarity. And anyway when you go the private insurance route, the way it's setup currently, you are giving away a huge percentage of your earnings to the insurance. They justify this by saying your gainz are only taxed at 50% of their actual value, but since one of the biggest problems of the world today is an overgrown financial strength (thus influence) of large corporations, caveat emptor.