Niklaus Wirth Quotations

In the practical world of computing, it is rather uncommon that a program, once it performs correctly and satisfactorily, remains unchanged forever.

But quality of work can be expected only through personal satisfaction, dedication and enjoyment. In our profession, precision and perfection are not a dispensible luxury, but a simple necessity.

Program construction consists of a sequence of refinement steps.

My duty as a teacher is to train, educate future programmers.

Many people tend to look at programming styles and languages like religions: if you belong to one, you cannot belong to others. But this analogy is another fallacy.

Our ultimate goal is extensible programming (EP). By this, we mean the construction of hierarchies of modules, each module adding new functionality to the system.

I have never designed a language for its own sake.

A good designer must rely on experience, on precise, logic thinking; and on pedantic exactness. No magic will do.

Software development is technical activity conducted by human beings.

Experience shows that the success of a programming course critically depends on the choice of these examples.

Indeed, the woes of Software Engineering are not due to lack of tools, or proper management, but largely due to lack of sufficient technical competence.

The idea that one might derive satisfaction from his or her successful work, because that work is ingenious, beautiful, or just pleasing, has become ridiculed.

The possible solutions to a given problem emerge as the leaves of a tree, each node representing a point of deliberation and decision.

Clearly, programming courses should teach methods of design and construction, and the selected examples should be such that a gradual development can be nicely demonstrated.

It is evidently necessary to generate and test candidates for solutions in some systematic manner.

My being a teacher had a decisive influence on making language and systems as simple as possible so that in my teaching, I could concentrate on the essential issues of programming rather than on details of language and notation.

Usually its users discover sooner or later that their program does not deliver all the desired results, or worse, that the results requested were not the ones really needed.

Yet, I am convinced that there is a need for high quality software, and the time will come when it will be recognized that it is worth investing effort in its development and in using a careful, structured approach based on safe, structured languages.

But active programming consists of the design of new programs, rather than contemplation of old programs.

Nevertheless, I consider OOP as an aspect of programming in the large; that is, as an aspect that logically follows programming in the small and requires sound knowledge of procedural programming.

The creative activity of programming - to be distinguished from coding - is usually taught by examples serving to exhibit certain techniques.

I know of a particular, very large software producer that explicitly assumes that design takes 20% of developers' time, and debugging takes 80%.

Programs should be written and polished until they acquire publication quality.

Software gets slower faster than hardware gets faster.

Go To statement considered harmful.

During the process of stepwise refinement, a notation which is natural to the problem in hand should be used as long as possible.

Reliable and transparent programs are usually not in the interest of the designer.

I am convinced that there is a need for high quality software, and the time will come when it will be recognized that it is worth investing effort in its development and in using a careful, structured approach based on safe, structured languages.

Good engineering is characterized by gradual, stepwise refinement of products that yields increased performance under given constraints and with given resources.

Programming is usually taught by examples.

Whereas Europeans generally pronounce my name the right way ('Ni-klows Wirt'), Americans invariably mangle it into 'Nick-les Worth'. This is to say that Europeans call me by name, but Americans call me by value.

Our ultimate goal is extensible programming. By this, we mean the construction of hierarchies of modules, each module adding new functionality to the system.

Software is getting slower more rapidly than hardware becomes faster.

Prolific programmers contribute to certain disaster.

Increasingly, people seem to misinterpret complexity as sophistication, which is baffling -- the incomprehensible should cause suspicion rather than admiration.

Software gets slower faster than hardware gets faster. (Or, sometimes known by] Grove [the head of Intel] giveth and Gates [the head of Microsoft] taketh away.)

Professors typically spend their time in meetings about planning, policy, proposals, fund-raising, consulting, interviewing, traveling, and so forth, but spend relatively little time at their drawing boards. As a result, they lose touch with the substance of their rapidly developing subject. They lose the ability to design; they lose sight of what is essential; and they resign themselves to teach academically challenging puzzles.

Time pressure gradually corrupts an engineer's standard of quality and perfection. It has a detrimental effect on people as well as products

The belief that complex systems require armies of designers and programmers is wrong. A system that is not understood in its entirety, or at least to a significant degree of detail by a single individual, should probably not be built.

A primary cause of complexity is that software vendors uncritically adopt almost any feature that users want.

C++ is an insult to the human brain

Complexity has and will maintain a strong fascination for many people. It is true that we live in a complex world and strive to solve inherently complex problems, which often do require complex mechanisms. However, this should not diminish our desire for elegant solutions, which convince by their clarity and effectiveness. Simple, elegant solutions are more effective, but they are harder to find than complex ones, and they require more time, which we too often believe to be unaffordable