3. 글의 흐름으로 보아, 주어진 문장이 들어가기에 가장 적절한 곳을 고르시오.
It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties.
The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. ( ① ) With time, they discovered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery and various metals. ( ② ) Furthermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. ( ③ ) At this point, materials utilization was totally a selection process that involved deciding from a given, rather limited set of materials, the one best suited for an application based on its characteristics. ( ④ ) This knowledge, acquired over approximately the past 100 years, has empowered them to fashion, to a large degree, the characteristics of materials. ( ⑤ ) Thus, tens of thousands of different materials have evolved with rather specialized characteristics that meet the needs of our modern and complex society, including metals, plastics, glasses, and fibers.
[4 ~ 5] 다음 글을 읽고, 물음에 답하시오.
Our irresistible tendency to see things in human terms ― that we are often mistaken in attributing complex human motives and processing abilities to other species ― does not mean that an animal’s behavior is not, in fact, complex. Rather, it means that the complexity of the animal’s behavior is not purely a (a) product of its internal complexity. Herbert Simon’s “parable of the ant” makes this point very clearly. Imagine an ant walking along a beach, and (b) visualize tracking the trajectory of the ant as it moves. The trajectory would show a lot of twists and turns, and would be very irregular and complicated. One could then suppose that the ant had equally complicated (c) internal navigational abilities, and work out what these were likely to be by analyzing the trajectory to infer the rules and mechanisms that could produce such a complex navigational path. The complexity of the trajectory, however, “is really a complexity in the surface of the beach, not a complexity in the ant.” In reality, the ant may be using a set of very (d) complex rules: it is the interaction of these rules with the environment that actually produces the complex trajectory, not the ant alone. Put more generally, the parable of the ant illustrates that there is no necessary correlation between the complexity of an (e) observed behavior and the complexity of the mechanism that produces it.
4. 윗글의 제목으로 가장 적절한 것은?