Question from the audience: There is a sharp contrast... Hassan Nagib said that engineering is close to science. Professor Guralnick said that engineering is not applied science...

Hassan Nagib: There is a broad spectrum of engineers. There is a broad spectrum of scientists. Obviously, when you take a look at scientists you have the very pure or basic scientists and then you have the more applied scientists. In engineering, the extreme away from science is the design or product engineer. Particularly for the edge of development, new innovation, new breakthroughs, it is really the other group of engineers that is closest to science. A design engineer is not different in many ways from an architect. There is almost an artistic element to a design engineer and you can see that particularly in Sid's comments. I've heard this in other talks on engineering. Aerodynamists talk about a good-looking airplane, not necessarily a high performance airplane, just good-looking, aesthetically pleasing. So, it is important to recognize that while science is a way of revealing the secrets of nature, good engineering is a way of taking the secrets of nature and applying them to solve problems. The closeness needs to be there.

Sid Guralnick: Perhaps I should be more precise. By "engineering;' I mean engineering design. Engineering design is not applied science. Engineering design implies a significant set of creative activities. One must first imagine the artifact -be it a building, a pen, an automobile, whatever. The engineer need not know that in a correct interpretation of Newton's Second Law, force is not necessarily mass times acceleration but is always the time derivative of the momentum. It's really not important for the designer who conceives of a new product, process, or system to know that fine point. What is important is that the designer utilize his or her imagination and then take the product of that imagination and render it on paper or in a computer.

Now, having rendered the product of imagination on paper or in a computer, the engineer can use science to predict the behavior of that artifact, process, or system when it is placed in service. That's where science comes in. The engineer uses science, but does not do what a scientist does. The scientist's task is to discover the nature of Nature. The task of the engineer, who is doing engineering design, is not to discover the nature of Nature. His task is, first, to conceive of a product, process, or system and, second, to predict its behavior in service using whatever science he can bring to bear on the problem.

The modern engineer differs from his earlier counterparts. They did not have science to predict the behavior in service of their products, process, or systems, but they still had the task of creating these artifacts. They had to use trial and error instead of science. You may remember from accounts of the construction of the great Gothic cathedrals that when the centering or framework was removed, the roof sometimes collapsed. When this occurred, the cathedral was rebuilt, using a somewhat different roof support system. There was no science available during the Gothic age to enable an accurate prediction of how a massive roof structure would behave under load. That's the real difference between modern engineering, which is a product of the scientific revolution, and engineering of an earlier era.

The task of the engineer remains the same, however, and that's what I'd like to emphasize. There is no difference between the essential task of the Roman or Gothic engineer and the essential task of the modern engineer. The task remains the same-to create works that people must use and that people desire-that society desires and needs. Scientific knowledge is used in engineering to predict the behavior of an artifact without first using it; that is, to avoid the nasty surprise of pulling away the centering to find that a newly constructed (and expensive) roof collapses.

Hamid Arastoopour: In the last five years, even in the last year, science and engineering have been brought much closer together by the computer-the power of processing. Problems that I can solve today, I could not solve last October because the power of processing was not adequate. Super-computers now allow us to discover phenomena that we couldn't believe existed. We are now looking at viscosities, pressures, and temperatures, we go to the molecular activities and try to develop these processes for the multi-phase system -something that no scientist or engineer would have believed a few years ago. It wasn't possible before we got computer data acquisition. Now I can get a thousand data points in seconds. I can see the phenomena. I can make discoveries and use them. I hope that if I talk to you two years from now, I will be able to tell you much more.