Henry Petroski

In a nutshell

The Essential Engineer is about the similarities and differences between scientists and engineers, and between science and engineering, and how they relate to contemporary technological issues. The book provides historical background to the distinctions between science and engineering and considers their relevance for solving today’s global problems.

I emphasize that science, in its purest form, working alone, is not likely to solve problems relating to climate and energy issues; it is important for science and engineering to work together in meeting the technological challenges that face the world.

The Essential Engineer also describes opportunities that have been presented to scientists and engineers today in the form of a host of challenges and prizes offered to stimulate research and development in important areas of need. (These range from the mundane, say the search for a more efficient battery, to the exotic, say space travel and exploration as private enterprise.)

The wide angle

This book relates to the nature and to the practice of research and development. I write as an engineer who has been involved with many aspects of the profession, including design, research and development in the nuclear industry, and teaching at both the undergraduate and graduate levels.

The central topic is how research and development has been, can be, and might be funded and practiced to improve effectiveness in producing results that are relevant to problems facing the world today. Rather than being at odds with each other, research and development should be seen as two aspects of the same endeavor; sometimes the one takes the leading role, and sometimes the other.

Many significant engineering developments have been advanced without full scientific understanding of the phenomena involved. This situation has often forced engineers to engage in scientific exploration and experimentation in the absence of scientific interest or motivation to do so. The lessons learned from historic case studies should be encouraging to inventors and engineers engaged today in efforts to develop new devices and technologies even in the face of incomplete scientific knowledge.

There is much debate today about choices and strategies involving alternative energy sources. In the book, I weigh the pros and cons of many of them. Among the energy sources I discuss are bio, solar, wind, wave, tidal, geothermal, etc. Also, I pay some attention to the various pros and cons of all-electric, hybrid, plug-in hybrid, and other variations of more fuel efficient vehicles.

A close-up

Chapter 3, entitled “Which Came First?”, goes over a number of examples of engineering achievements that were accomplished without full scientific understanding or explanation of the phenomena involved. Among those examples are rockets, which preceded rocket science; the steam engine, which preceded thermodynamics; powered flight, which preceded a fully formed science of aerodynamics; and hybridization, which preceded genetics.

Such examples—and the implications they have for the way the world really works—should lead the general reader to a fuller understanding of the nature and practice of science and engineering. I hope that they will be encouraging to inventors and engineers who wish to pursue a goal even in the absence of full scientific support for their idea.

Lastly

The larger context of The Essential Engineer is its relevance to the world of public policy and legislation.

Since so much of what is considered by lawmakers today is necessarily technological at heart, there is great value in a book laying out clear distinctions between science and engineering and their relationship to the important political and economic goals of innovation and global competitiveness. Legislation intended to promote and support innovation, for example, may have just the opposite effect if it encourages only science, at the expense of engineering, and this should be emphasized to political leaders and lawmakers.

Unfortunately, the distinct endeavors of engineering, invention, and technology are often subsumed under the single rubric “science” and so are not highlighted in their own right. This lack of attention to the true sources of innovation can jeopardize our nation’s future. The Essential Engineer is one attempt to correct this situation.