Physics is designated as an experimental and exact science, laws which are based on facts established by experiment, and formulated using mathematics. It has such features thanks to Galileo.

Before Galileo "physics" - the study of nature - was part of the philosophy and based on the principles of Aristotle’s philosophy. This philosophy divided the world into heaven , where is the perfect circular movements that have neither beginning nor end, and the earth, where movements have a beginning and an end, and things are moving according to its nature (quality), particularly heavy fall down and the light rise up. Movements of objects are divided into natural and violent , and the properties of bodies " explains " by their "nature" ( quality).

Galileo proclaimed the need for a quantitative study of phenomena. He affirmed: “The book of nature is written in the language of mathematics, and the symbols are triangles, circles and other geometrical figures , whose help it is impossible to comprehend a single word of it; without which one wanders in vain through a dark labyrinth”; “Anyone who wants to solve problems without the help of science math puts an impossible task. “Measure what can be measured, and make measurable what cannot be measured.”

Galileo opposed to explain the properties of bodies of nature (quality) and in his works based on the ideas of opponents of the philosophy of Aristotle - ancient atomists ( materialists ). Atomists drew a picture of the world as “Sweet exists by convention, bitter by convention, color by convention; atoms and Void exist in reality” (Democritus); "... Atoms do not have any properties of objects available senses except shape, weight, size and all the goodies that are connected to the need for the form. Because every property changes, but the atoms does not change ... "( Epicurus ).

Galileo also affirmed “I never state from external bodies require anything other than size, shape, number and more or less rapid motions , in order to explain the origin of the senses of taste, smell and sound; and I think that if we removed the ears , tongues , noses , we would have only shapes , numbers and movements, but not the smells , tastes and sounds that , in our opinion, outside of a living being is nothing but only empty names ".

Based on this idea - to explain all the phenomena by the mechanical movements of environment and particle, to search phenomena of mechanism - created the theory of classical physics.

Galileo also developed an experimental method for the study of nature , which includes experimentation , their analysis, formulation based on certain assumptions and analysis of comprehensive experimental verification of these assumptions. In particular , this method was used in the study of falling bodies by Galileo. He started with the assumption that bodies fall with constant acceleration. With this assumption , Galileo got the conclusion that with the motion with constant acceleration, path that was traversed by a body is proportional to time squared. This conclusion Galileo tested by examining the movement of the balls on an inclined plane from different angles.

It is clear that in the ages that have passed after the studies of Galileo , physics significantly evolved and changed, but more importantly the fact that it was introduced into physics - searching for quantitative dependencies, searching phenomena of mechanism, combining theory and experiment - remains unchanged.

V. Ignatovych, c.t.s.