David Lorge Parnas

“It is almost always incorrect to begin the decomposition of a system into modules on the basis of a flowchart.”

“We are not in the business of building software, we are in the business of solving problems.”

“A data structure, its internal linkings, accessing procedures and modifying procedures are part of a single module.”

“It is a myth that we can get systems right the first time. Instead, we should make systems that are easy to change.”

“Instead of starting with a list of modules, we start with a list of secrets.”

“My own view is that the whole 'software crisis' is a symptom of a deeper problem: an unmastered complexity.”

“True professionalism is a matter of ethics, not a matter of style.”

“The 'right' way to design a system is to keep it simple, and the 'right' way to keep it simple is to hide information.”

“Design is the process of deciding what to hide.”

“I have found that the most difficult part of software development is getting the requirements right. If you get the requirements wrong, it doesn't matter how well you code, the system will be a failure.”

“The primary goal of software design is to manage complexity.”

“Fake it. If you don’t know how to solve the problem, write the interface to a module that can. Then write the module.”

“Software is a mirror of the mind of the designer.”

“We must not be afraid to stop work on a project if we realize that our initial assumptions were wrong.”