Mainstream physics currently contends that only 4% of our Universe is made of normal matter and energy. The remaining 96% is thought to be mysterious dark matter and dark energy that are not at all understood. This presents a quandary relative to Einstein’s observation: “The most incomprehensible thing about the world is that it is comprehensible.” Using judicious analogies, dry humor, and the established laws of physics, Ron Forth presents a new cosmological paradigm, honouring the principles of classical physics and relativity while examining the astronomical observations and ensuing inferences from a fresh perspective. Beginning by replacing curved spacetime with contoured four-dimensional space-energy, a new theory of gravity is developed. Using logical and mathematical arguments, he explains how forces, inertia, and entropy arise within this framework. Topics including black holes, gravitational waves, unification of the four fundamental forces, and the probabilistic nature of quantum mechanics are touched upon in the context of the model. He shines a light on dark matter and dark energy, potentially dispelling their shadows. A possible ultimate fate of the Universe, a topic of interest to most of its inhabitants, is proposed. Covering the life of the Universe in a compact book, The Forth Dimension may prove revolutionary – or not - but it will hopefully provoke further discussion of our understanding of the Universe. The objective is for professional scientists to consider the implications of the philosophy, hypotheses, and analysis presented. Various tests are proposed to experimentally determine whether the ideas are science or science fiction.