Question

How do we know at what point we can consider our environment to be secure?

Answer 1

Our environment can never be fully secure, but steps can be taken to make our environments reasonably secure

Answer 2

It is said that one can never be too sure, based on this saying, our environment can never be said to be fully secured, or we can never assume or believe that our environment is absolutely secure, however, steps can be taken to make our environments reasonably secure.