The so-called "theory of everything" (T.O.E.) of reality cannot be perfect, if it ignores reality of the mind, from where we are looking at, researching, and describing reality as it is. One cannot progress very far in answering the metaphysical questions about reality without considering problems about time. Because time is the most crucial of all metaphysical and physical problems, it must be resolved in order to find a T.O.E. A German theologian, Karl Heim (1874-1958), gave a notable ontological answer to the enigmatic problem of time. In his T.O.E., time is two-dimensional space. Contents: An Outline of Heim's Dimensional Thinking - The Philosophical Background of the Dimensional Theory: Kant, Fichte, Schelling, Hegel, Natorp, Rickert, Husserl, Heidegger, Einstein, and Heisenberg - The Basic Concepts: Space, Boundary, and Polarity/ The Dimensional Theory and its Contributions to Philosophy, Science, and Theology.