Transportation and Logistic System

A system is difficult to define, but it is easy to recognize some of its characteristics. A system possesses boundaries which segregate it from the rest of its field: it is cohensive in the sense that it resists encroachment from without...

When Newton first discovered the property of attraction, and settled its laws, he found it served very well to explain several of the most remarkable phenomena in nature ; but yet with reference to the general system of things, he could consider attraction but as an effect, whose cause at that time he did not attempt to trace. But when "he afterwards began to account for it by a subtile elastic æther, this great man (if in so great a man it be not impious to discover any thing like a blemish) seemed to have quitted his usual cautious manner of philosophising; since, perhaps, allowing all that has been advanced on this subject to be sufficiently proved, I think it leaves us with as many difficulties as it found us. That great chain of causes, which links one to another, even to the throne of God himself, can never be unravelled by any industry of ours. When we go but one step beyond the immediately sensible qualities of things, we go out of our depth.

In the most abstract sense, a system is a set of objects together with relationships among the objects. Such a definition implies that a system has properties, functions, and dynamics distinct from its constituent objects and relationships.