Robert E. Machol Quotes

The purpose and real value of systems engineering is... to keep going around the loop; find inadequacies and make improvements.

If the assumptions are wrong, the conclusions aren't likely to be very good.

Sometimes, where a complex problem can be illuminated by many tools, one can be forgiven for applying the one he knows best.

Most accidents in well-designed systems involve two or more events of low probability occurring in the worst possible combination.

There are four distinct bases on which a system-design book might be organized. First are the chronological phases through which the system-design effort passes, such as organization and preliminary design. Second are the logical steps such as analysis of the single thread (operation on a single input) and high traffic (methods of handling multiplex inputs). Third are the parts of the system, such as communications and displays. Fourth are the tools of system design, such as information theory and queueing theory.

Scientists possess healthy skepticism. They realize that you've got to know the answer before you measure it.

In April of 1959, ten of this country's leading scholars forgathered on the campus of Purdue University to discuss the nature of information and the nature of decision... What interests do these men have in common?... To answer these questions it is necessary to view the changing aspect of the scientific approach to epistemology, and the striking progress which has been wrought in the very recent past. The decade from 1940 to 1950 witnessed the operation of the first stored- program digital computer. The concept of information was quantified, and mathematical theories were developed for communication (Shannon) and decision (Wald). Known mathematical techniques were applied to new and important fields, as the techniques of complex- variable theory to the analysis of feedback systems and the techniques of matrix theory to the analysis of systems under multiple linear constraints. The word "cybernetics" was coined, and with it came the realization of the many analogies between control and communication in men and in automata. New terms like "operations research" and "system engineering" were introduced; despite their occasional use by charlatans, they have signified enormous progress in the solution of exceedingly complex problems, through the application of quantitative ness and objectivity.

[This set of inputs [can be defined] as 1) input which is always the same or is of many types, 2) input which occurs periodically (or very infrequently), and 3) input which does or does not seek to destroy the system. Their rationale for developing the classification was to aid in the definition of steps to be followed in order to find the] solution of the problem of a large-scale or complex system.

The ideal system engineer is an engineer thoroughly versed in his field but conversant with and knowledgeable of other fields. You have to have the capability and desire to become a 'six-month expert'... You've got to want to become a generalist, too.

The lack of formal definition does not prevent us from noting the characteristics which are frequently present in large scale systems. Each such system has a certain integrity. It may or may not be rigidly controlled from some central point, but in every case, all the parts of the system have some common purpose; in some sense, they all contribute to the production of a single set of optimum outputs from the given set of inputs, with respect to some appropriate measure of effectiveness.

The conclusions of most good operations research studies are obvious.

[Systems should be classified] on the basis of the types of inputs with which they must cope.

Every large-scale system is an . The automatic factory, the vehicular-traffic system, any military system- in the design of all these systems, primary attention should be given to the flow of information about the elements of the system.

Management has a design and operation function, as does engineering. The design is usually done under the heading of organization. It should be noted first that the performance of a group of people is a strong function of the capabilities of the individuals and a rather weak function of the way they are organized. That is, good people do a fairly good job under almost any organization and a somewhat better one when the organization is good. Poor talent does a poor job with a bad organization, but it is still a poor job no matter what the organization. Repeated reorganizations are noted in groups of individuals poorly suited to their function, though no amount of good organization will give good performance. The best architectural design fails with poor bricks and mortar. But the payoff from good organization with good people is worthwhile.

There comes a time when one must stop suggesting and evaluating new solutions, and get on with the job of analyzing and implementing one pretty good solution.