In 1936 Silberstein proposes a fairly straightforward discrete theory. The only thing we use in physics are labels, \(x, y, z, t\) and, when discrete, these can always be labelled with integers. In the short booklet that brings together the five lectures on this theme, Silberstein restricts himself to one spatial and one time parameter. Although he acknowledges the problem (1936: 15) of higher dimensions, he does not deal with it. So the distance problem becomes rather trivial since on a line, the discrete distance function and the Euclidean distance function coincide. His proposal is elementary in the sense that the smallest distance, viz. the distance between two adjacent points \(x_{i}\) and \(x_{i+1}\) is equal to 1 and likewise for the time coordinate, so that 1 becomes the maximum velocity, put equal to \(c\), so \(c = 1\). Analogs for derivatives are defined, differential equations are replaced by difference equations, an analog in terms of finite differences is derived of the Taylor series and most of classical physics can be imitated. It is worth mentioning that the lectures include a rough calculation of the size of the chronons, i.e., the smallest unit of time, and hodons, i.e., the smallest unit of (one-dimensional) space. Suppose that \(a\) is the number of hodons in one centimetre and \(b\) the number of chronons in one second, then \[ \frac{(1/a)}{(1/b)} = \frac{b}{a} = c = 3.10^{10}\text{cm/s,}\quad \text{ or }\quad b = 3.10^{10}\cdot a.\] If we fix a lower limit for \(a\), say \(10^{-8}\) cm (this is actually Silberstein’s suggestion!), then \(b = 3.10^{10}\cdot a \geq 3.10^{18}\), being the number of chronons in one second. He further applies the discrete spacetime framework to special relativity and here too, an analog is found. Quite interesting in this approach is the fact that additional conditions appear that are not needed in the classical case. Here is one illustration.