Natural resources are infinite. This is possible because humans can create theories whose potential goes beyond the limited imaginative capacity of the inventor. For instance, no number of people can work out all the economic potential of quantum theory. Economic Resources are created by an interaction of Karl Popper's Worlds 1, 2 and 3, the worlds of physics, psychology and the abstract products of the human mind, such as scientific theories. Knowledge such as scientific theories has unfathomable information content, is (...) universally applicable, and infinitely copyable. The point can be made with technological knowledge such as that embodied in the wheel. The theory of the wheel has un- bounded potential to be embodied in unforeseeable new technologies, is useful on the Moon as on Earth, and can be infinitely copied. Unlike a piece of land (using fixed factors), such knowledge shows increasing returns. This helps to explain Julian Simon's observation that "natural" resources are now less scarce than they used to be and why an increasing population can increase resources in the long-run. It was Simon's breakthrough to elaborate on the abstract character of "natural" resources. I further explore this abstract character and thereby explain why natural resources are infinitely expandable. Economic growth and the creation of natural resources depends on the rate of invention. F. Machlup's suggestion (Machlup 1962) that the opportunity for new inventions increases geometrically with the number of inventions at hand is acknowledged for its suggestiveness, but criticised for its conservative position. Frank Tipler's fascinating argument for indefinite economic growth (Tipler 1994), is reinforced by my argument by making a distinction between information in the engineer's sense and the infinite potential "information" in our scientific knowledge based on Popper's notion of information content. (shrink)