So we have made an agreement, based on Newtonian principles, such as gravity, mass, weight, optics, the way light behaves, how sound waves behave, etc. We set a norm as a baseline or we wouldn’t be able to communicate with each other about any given subject. We all agree that the test tube contains a red substance, even if it appears black to a cat. And we can go from there in our explorations of our physical environment.
But the quantum physicist understands that this reality we perceive is not the total picture. It is what our senses allow us to experience so we can navigate through life and survive. They know that what is invisible is even more important that what is visible.