What is the difference between engineering and science?

Engineers and scientists have a friendly rivalry.  A recent book The Essential Engineer - why science will not solve our global problems by Henry Petroski provides some quotable arguments:

"A scientist studies what is; an engineer creates what never was. By extension, science is the study of what is; engineering is the creation of what never was."

"Science is about knowing; engineering about doing."

"Engineers do not need to imagine the unimaginable; they have to imagine the manageable."

"As engineers, we were going to be in a position to change the world—not just study it."

"It is customary to think of engineering as a part of a trilogy, pure science, applied science, and engineering. It needs emphasis that this trilogy is only one of a triad of trilogies into which engineering fits. The first is pure science, applied science, engineering; the second is economic theory, finance, and engineering; and the third is social relations, industrial relations, engineering. Many engineering problems are as closely allied to social problems as they are to pure science."

FIVE KEY DIFFERENCES

1. Science is about discovery, while engineering is about innovation.
2. Science starts with a question, while engineering starts with design.
3. Science is the study of knowledge, while engineering is the study of applications.
4. Science uses various approaches to study, while engineering uses particular approaches to find solutions.
5. Science understands new concepts, while engineering understands constraints to design solutions.

Therefore, science is the body of knowledge that explores the physical and natural world, while engineering is the application of knowledge in order to design, build and maintain a product or a process that solves a problem and fulfills a need.

This page was last updated 31 March 2025.