The number/concept "zero" wasn't invented, it was discovered. It had been there all along, undiscovered. Unnoticed. Without having discovered it, much of science was impossible to really do, and much of reality was impossible to understand.
So it is with Zero Aggression Principle and property rights. No one invented the concepts- they were independently discovered many times- by many, mostly anonymous, individuals- throughout history.
Without those features of reality, humans suffer needlessly. Without them, bad guys flourish and prosper. With them, civilization happens.
People may complain that "zero" is "nothing"- only an imaginary thing dreamed up inside the head of people who think about such things. You can't "see it" or touch it. Maybe. But it's still real and necessary.
So it is with the only civilized ways to interact with other people: living by the ZAP and respecting their property rights.
You can deny it, fight it, ridicule it... and it is still there. It would be there even if no one had yet discovered it.