If you read enough security literature, eventually you'll come across the notion of a "trusted system". And your first impression will be that this is a system

If you read enough security literature, eventually you'll come across the notion of a "trusted system". And your first impression will be that this is a system which is fully debugged and tested and you can trust it to do its job within specifications. But you couldn't be more wrong. A trusted system is one which you have to trust. No representations are made about whether you should or not. Humans are frequently trusted systems.