John Scalzi

In the orientation session I received when I joined the organization as a technician, I was provided a brief gloss of the physics involved, and how the intervals were due to quantum fluctuations and nested dimensions and other such abstruse concepts.

I appreciated that the organization wanted me to understand these things, but at the end of the day I was hired to push buttons, move the clients through the exit and reentry process, and, when needed or desirable, call a supervisor. These tasks do not require an advanced degree. They barely require sentience. But the organization had learned over time that the presence of another human settles the clients (who are not told the internal name for them is “clients”—they are informed that they are referred to as “temponauts”). It is psychologically important, when traveling through time, to have another human be the last and first thing you see.

“History” stops being accurate the moment you observe it.

You can’t be “careful” and attempt to interact only minimally; one can’t know which actions, however seemingly trivial, will be directly consequential, immediately or over time.