Space
The container and fabric of existence
5 attributes · Dimension II
Overview
Space is the dimension of extension, location, and separation. It is what makes it possible for two things to be distinct — in different places — and yet related, by the distance between them. To exist in space is to be somewhere rather than nowhere, to have neighbors and horizons, to be able to move and be moved. Without space, matter could not be distributed, forces could not act at a distance, and no observer could be said to be here rather than there.
Philosophical Significance
The philosophical debate about space has a surprisingly clear structure. Newton argued for absolute space: an infinite, unchanging, three-dimensional container that exists independently of anything it contains. The bucket experiment, he claimed, showed that rotation was real and could only be real relative to absolute space. Leibniz disagreed: space is purely relational — it is nothing but the set of spatial relations among material things, and an "empty" space would be no space at all. Kant cut through the debate by making space a form of intuition: neither an independent substance nor a set of material relations, but the mind's own framework for organizing outer experience. Modern physics has partly vindicated all three: space is relational in that matter curves it, yet it has independent dynamical degrees of freedom (gravitational waves), and it is, in Kant's spirit, inseparable from the conditions of any possible observation.
Scientific Perspective
Euclidean geometry was, for two millennia, the geometry of space — flat, infinite, and uniform in all directions. Non-Euclidean geometries (Gauss, Riemann, Lobachevsky) showed that other geometries were mathematically consistent. Einstein's general relativity realized this: the universe's actual spatial geometry is non-Euclidean, curved by matter and energy. On cosmic scales, space may be finite (a closed universe) or infinite (a flat or open one); current measurements favor a nearly flat, very large universe. String theory posits up to ten or eleven spatial dimensions, most compactified at scales too small to observe. Quantum gravity approaches such as loop quantum gravity suggest space itself may be quantized — composed of discrete units, not a smooth continuum.
Key Philosophical Debates
The Newton-Leibniz debate continues in modern form. Substantivalism holds that spacetime is a real entity with its own existence, distinct from the matter it contains. Relationism holds that spacetime is nothing over and above the relations among physical objects and events. The "hole argument" in general relativity (Earman and Norton) suggests that substantivalism leads to indeterminism, but relationists face their own problems accounting for the dynamical degrees of freedom of spacetime itself.
Three large spatial dimensions appear to be a contingent fact about our universe, not a logical necessity. In three dimensions, gravitational and electrostatic forces obey inverse-square laws — a consequence of the geometry. In other numbers of dimensions, stable planetary orbits would be impossible. The "anthropic" explanation notes that only universes with three large spatial dimensions could contain observers; but this raises deep questions about why three rather than some other number.
Classical physics and general relativity treat space as a smooth continuum — any region of space can be subdivided indefinitely. Quantum gravity suggests this may break down at the Planck scale (about 10⁻³⁵ meters), below which the concept of "distance" may become meaningless. If space is discrete at this scale, the continuous geometry of general relativity is an approximation — as fluid mechanics is an approximation to the discrete structure of molecules.
Across Philosophical & Theological Traditions
Ancient Greek philosophy distinguished between place (topos — the boundary of a containing body) and void (kenon — empty space). Aristotle denied the void; the Epicureans embraced it. Medieval Islamic and Christian philosophers largely followed Aristotle in rejecting infinite empty space, associating spatial infinity with God alone. Newton's absolute space was sometimes identified with God's omnipresence (the "sensorium of God"). Phenomenological traditions (Merleau-Ponty, Heidegger) emphasize lived space — the embodied, oriented, affectively charged space of human existence — as more fundamental than the abstract geometric space of physics. Reformed theology holds that God is omnipresent (not confined to any spatial location), while creatures are spatially finite — a distinction that marks the unbridgeable difference between Creator and creature.
Attribute Definitions
Extent
Ontological Status
Curvature
Dimensionality
Locality
Space in Dimension Pairs
Space in Dimension Triplets