I like to think that things are even more complicated, as we depend on a lot of people, even if we are not aware of it: random taxi/bus drivers, restaurant/grocery staff, your ISP workers, random factory workers, etc.

We depend on far mote people than we realize, and not just us but also people working in advancing the limits of human knowledge. We wouldn’t have Einstein without some of his totally unexpected yet unkownly related contemporanies. Following this logic, we wouldn’t have Einstein without his grandparents, and even those grandparent’s contemporanies, and this just keeps going.

As Lain says, we are all connected.