This book, which is the fourth edition of the Eigen Theory of the Physical World, presents the eigen theory of the natural physical world of geometrical origin the principal feature of which happens to be the proper form of dark matter. According to this theory the fundamental form of a particle of matter is a continuous distribution of points that forms a manifold of its own. Each of these points results from the intersection of a corresponding pair of eigen velocity vectors that generate the wave aspect of the wave-particle duality of matter. The theory evolves in three stages. The first stage develops the pair of eigen velocity vectors. These vectors are complete with their own field of a pair of symmetric and antisymmetric tensors characteristic of gravitation and electromagnetism respectively. The second stage transforms the wave aspect into its very opposite, the particle aspect, as a pair of particles that are the progenitors of proton and electron. The base manifolds of these particles are made up of the proper form dark matter. The third stage brings together proton and electron as the Hydrogen atom which in effect is the proper particle aspect of the wave-particle duality of matter. In the eigen theory General Relativity becomes complete and Quantum Mechanics gets restructured; in particular the principle of uncertainty ceases to exist.