Throughout 20-th century the art field has expanded to proximate areas such as industrial objects (ready made, installation) or as social reality (performance art, happening). Expanding its limits into the body of science too is a natural next step under this trend. And that new art field can be called theoretical art. Some of it had been done before naturally by scientists but also by proper artists. Some conceptualists did it under the criteria that I pointed out in the book, but mainly accepted today as conceptualism. I believe that theoretical art goes beyond the conceptualism to the very field of science and therefore fundamentally differs from it in many aspects. That is precisely going to be shown in details in this book.