A body of knowledge is established, eventually labelled as classical physics or classical science, which involves a way of seeing the world with the following features:

• Matter, which tends to be viewed as discontinuous in its structure, moves through space and time according to the laws of mechanics. These laws are such that if one knows the state of a system at a given time, it is feasible to determine that state at any time in the past or future. The evolution of the physical world is therefore deterministic.
• All the apparently qualitative differences in nature, the appearance that things present, are due to the differences of configuration or the movement of certain basic units or their aggregates. The qualitative changes are therefore mere superficial effects of the displacement of these elementary units.
• The reciprocal action between basic corpuscles is not an action at a distance; it can always be explained by a series of successive actions of the medium that separates the interacting bodies (this subtle medium is the ether).
• Energy can spread from one place to another by two alternative and excluding modes: by means of particles or through waves.
• The properties of a system, including atomic ones, can be measured with unlimited precision; it is sufficient to reduce the intensity of the measure unit or to introduce a controlled theoretical adjustment.

This view, which requires a certain way of understanding space, time, matter and motion, involves the acceptance of mechanical causality where the world, whose objective existence is not questioned, evolves in a clear and deterministic way, governed by laws formulated by differential equations.

Thus, science during the 18^th and 19^th centuries is aware of the rise and triumph of the so-called classical model, although late in that period the first cracks become visible that will lead to the end of the century crisis and the transit to a new paradigm.