The consequences of bad science are many. Bad science can send scientists on a wild goose chase, at least for a time, and use up money and resources. Bad science can also mislead the general public about facts, or about the certainty or uncertainty of our current knowledge in some field. Bad science can find its way into public policy or economic decisions. The worst cases of bad science involve fraud with immediate consequences for the safety of the public, such as false claims about the efficacy of a drug or the toxicity of a substance. But in general, the product of science is knowledge, and knowledge can be used for good or evil.

Bad engineering is of more immediate danger to the public. Can openers that cut off fingers, cars that blow up, nuclear power plants that melt down, can maim, kill, or terrify innocent people. The ultimate cause may be some fault in calculations or design, or simply neglecting to take into consideration that humans are involved. Good engineering has to outsmart the human capacity for mistakes.

Some major disasters that look like products of bad science or bad engineering may in fact have another cause. For example, the warped mirror of the Hubble telescope was the result not of bad science or even bad engineering: politicians and bureaucrats made a budgetary decision not to test the telescope before sending it up and so missed a technician's error.

We are shocked by fraud in science and failures in engineering. Why? The answer is that we take for granted good science and good engineering. But what is good science? What is good engineering? Do scientists and engineers have different ideas about this, or is there a consensus? Can it be spelled out? How can students be taught to do good science or good engineering?

With a science and engineering faculty strongly committed to both research and teaching, IIT seems to be a good place to discuss these questions. Such a discussion took place this fall as part of IIT's Centennial, sponsored by the Program on Science and Technology in Context, the Center for the Study of Ethics in the Professions, and the Department of Civil Engineering. This issue of Perspectives is drawn from that discussion. Our first section, The Importance of Being Earnest, consists of three scientists' views of good science: Bob Filler (chemistry), Ben Stark (biology), and Porter Johnson (physics).

Good engineering is discussed in the second section, Doing the Right Thing, by Hamid Arastoopour (chemical engineering), Janine Larsen (electrical and computer engineering), and Hassan Nagib (mechanical and aerospace engineering).

In the third section, The Good, the Bad, and the Ugly, Sid Guralnick (civil engineering) argues that engineering is a strikingly different intellectual activity from science, strongly dependent on imagining what does not yet exist. The next section, Close Encounters, further clarifies the relation between science and engineering.

Professors of science and engineering try to teach how to do good work. Things Change takes up the question of how to teach good science and good engineering in fields where change is both constant and profound. The discussion concludes with some thoughts about funding research, For a Few Dollars More.

Much remains to be said. The important thing is to continue the discussion. IIT's Centennial panel made a good start.