What is less complete, more partial, is less real than what is more complete, less partial.
Illustration: We say that the story of World War II given in a chapter of an elementary school textbook is "less realistic" than that offered in the multivolume work of a master historian.
The textbook version leaves out very many important details offered in the master historian's account.
Illustration: A boy is scared by a stuffed tiger in a museum. His parents tell him, "Wait until you see a real tiger!"
The stuffed tiger is less real because it is missing things that a living tiger has, in particular, whatever it is that gives living creatures their life.
Illustration: We say a blueprint of a house is "less realistic" then a scaled down model of the house. The blueprint has fewer characteristics of the real house than does the model: It is merely lines, while the model has walls, windows, a roof, doors, etc.
Illustration: I know Bill only from online chats. His friend tells me, "You don't really know Bill until you've gone out and had a few pints with him!"
The version of Bill that I know is less complete, more partial than the version his friend knows.
Illustration: The world of physics is an abstraction from the world of experience. From the world of experience, which contains sights, sounds, textures, smells, feelings of heat, feelings of cold, pain, pleasure, and so on, physics abstracts only what is measurable using physical measuring devices. It is a small subset of the world of experience.
QED: The world of physics is less real than the world of experience.
Note: This does not mean that the world of physics lacks all reality. It is an important and useful abstraction from the world of experience, in much the same way that a blueprint is an important and useful abstraction of a real house. Because the abstraction is performed according to very particular and coherent procedures, it can be manipulated in ways that reveal to us important new things about the world of experience, much as an accurate blueprint of a house can reveal to us new things about the house: "Hey, I think there is a secret room there in the middle!"
Acknowledgment I: I want to thank Keshav for pushing me to render what I intuitively understood in a more explicit form.
Acknowledgment II: This entire post came to me while I was walking the "Path of seeing" in the woods at the Kadampa Meditation Center. I guess the path did its job!