… is a necessary rule of thumb for computer-based knowledge & design workers. But add the lesson of cloud computing:
Backups: If you don't have 3 copies, you aren't serious.
The standard redundancy for cheap cloud storage options is 3 copies. Anything less is reduced redundancy, sold at discount. You should have at least 2 backups, for instance both a home backup disk and a cloud drive or repo.
A big win, when you plan for multiple copies, is that you no longer need any of them to be highly reliable. What matters more is, how fast can you make another copy if one copy goes down?
In philosophy, if you think the answer is obvious you haven't understood the question
If Everett's Many Worlds interpretation of quantum mechanics is true, I will not only eat my hat, I will eat yours too.
In fact, if Many Worlds is true, you will buy a hat specifically for me to eat.
“If science shows we are composed of trillions of cells and no ‘magic ingredients’ then…”
The thought is blind to the fact that if there are such ingredients then they are ipso facto invisible to scientific tools. Your first-person subjective experience, for instance, is invisible to science. It can only be accessed by asking you to tell.
Physicalism, as an attempt to explain all of reality, has a selective vision problem: it rules out anything it can't see.