They used the pension money for other things so it's logical to pay it back. And just because tax money is used for pensions doesn't mean the socuial security and pension contributions are tax burden.

Like I said, if all social security was through private insurance the tax burden would be lower but the people wouldn't have more money.

Health insurance proved otherwise. As long as you are healthy you pay less but as soon you get sick more often it gets way more expensive.

But the later wouldn't be recognized as tax burden.

Tax burden itself is a useless measure, the total cost of living is better.

>Like I said, if all social security was through private insurance the tax burden would be lower but the people wouldn't have more money.

It won't be that lower. The German pension has existing liabilities that they must pay. Since it is backed by the state, it will inevitably be paid by the taxes.

Even if the pension payments were abolished, just to pay existing entitlements, the taxes would be increased proportionally. The public pension can be considered a plus in a young country with a healthy demographics. In a geriatric state such as Germany, it is a big burden.