Caption: An ancient Greek hoplite.
Features:
The physical celestial sphere of the stars mutated into the modern imaginary, but very useful, celestial sphere.
Aristotelian cosmology offers no explanation to the spear paradox.
The atomists---most prominently Leucippus (first half of 5th century BCE, Democritus (c.460--c.370 BCE), Epicurus (341--271 BCE), and Lucretius (c.95--c.55 BCE)---did posit an infinite universe.
An infinite universe is hard to imagine, but a bounded finite Aristotelian universe seems even less imaginable.
If the spatial geometry is curved, then the universe could be the surface 3-sphere, a "sphere" in 4-dimensional mathematical space that has a 3-dimensional surface. A 3-sphere is 3-dimensional n-sphere (or hypersphere) is also called a glome.
A 3-sphere universe would be finite, but unbounded. The spear paradox would be avoided.
The 3-sphere universe is possible in theory, but we don't know if the universe is actually like this. At present, it seems NOT.