This paper postulates a “Dark Matter Force and Pressure” and also gives a conceptual and mathematical description for the reason for choosing a “Vacuum Energy Perfect Fluid” model, and using the Schwarzschild Metric over the Einstein Metric, based on the concept of whether there is “Zero Pressure” impressed upon the surface of the Black Hole Event Horizon; And likewise, whether the “Volume Mass Density” and the curvature of space, space-time, or the gravitational field, surrounding a matter source is normal throughout the gradient of a gravitational field, or whether it is rarefied/condensed through the gradient of a gravitational field, and eventually becomes normal far away from the matter source. In this paper a general introduction into the basic concepts of a “Perfect Fluid” gravitation theory, and this bodes for the necessity of Non-Euclidean “Curved-Space” Geometry, and Spherically Symmetric Metrics, used for describing causality for “Gravitational” interaction of mass with space or “isotropic aether” space-time, and mass interaction with mass.