In general physics for Aristotle is the theoretical science, which has as concept the study of nature, a definition that is quite accepted also by the modern scientists.
In order, however, to be accurate in our thoughts about this definition, the meaning of both the words Physics and nature must be mentioned.
Physics, in addition, according to the philosopher has some characteristics, from which the main ones are the following:
Firstly physics is not concerning depicting ideas through form like triangle, but real matter with movement and changes such as air, wood, water and stone. Including of course general ideas essential to the study of such changes like time, place etc.
Moreover, according to the philosopher, this science in comparison with the theoretical science of numbers, the mathematics namely, can give to the man the great opportunity to gain control of nature and ease the suffering of his/her labour.
But what is nature for Aristotle?
It may means: a. the initial state of things, opposed to its state after the small changes have happened by culture and education, b. the zenith of development that is achieved when every intrinsic power has been brought out, c. the inborn power of impulsive movement and change, and d. the aggregated tendency of bodies to display the movement which is persuaded by force.
Further, it seems that nature is also the power, which provides the proper characteristics of all the living beings in order to survive.
Nevertheless, physics, may be the theoretical science which has been developed through the high desire of man to follow the truth of things that he is powerless to change.
To you my friend and followers of the truth.