The ancient Greeks found *nothing* to be a very controversial concept. The world, throughout all ancient and many modern cultures, was believed to originate from *something*, whether it be the primal ocean or ur-matter or birthing by the gods.
Henning Genz recounts that the world was full, “there was no room for nothingness”. Democritus and the atomists found a use for empty space: it provides room for atoms to move. To maintain the primacy of the natural numbers, the Pythagoreans had to banish irrational numbers into the void. There is nothing between 1 and 2. Aristotle identified the void as the ground of distinction:
> The void distinguishes the natures of things, since it is the thing that separates and distinguishes the successive terms in a series. This happens in the first case of numbers; for the void distinguishes their nature.
Specializing in the virtual, mathematics accommodates the idea that there must be something by filling in the potential void with dimensionless objects called **points**. Genz again:
> To the mathematician, space is nothing but an ensemble of points that are connected by some set of relations. In this interpretation, the laws of nature that apply to objects, including our probes, have nothing whatever to do with the properties of the space around them.
[…]
⇒ Zero
~
William Bricken, Iconic Arithmetic Volume I: The Design of Mathematics for Human Understanding (Unary press, 2019), p. 163.