"It is commonly said that a pattern, however it is written, has four essential parts: a statement of the context where the pattern is useful, the problem that the pattern addresses, the forces that play in forming a solution, and the solution that resolves those forces. … it supports the definition of a pattern as "a solution to a problem in a context", a definition that fixes the bounds of the pattern to a single problem-solution pair"

“Modeling Principle: Models are not right or wrong; they are more or less useful.”

“Martin Fowler home page”

“Any fool can write code that a computer can understand. Good programmers write code that humans can understand.”

“Comprehensiveness is the enemy of comprehensibility”

“People also underestimate the time they spend debugging. They underestimate how much time they can spend chasing a long bug. With testing, I know straight away when I added a bug. That lets me fix the bug immediately before it can crawl off and hide. There are few things more frustrating or time-wasting than debugging. Wouldn't it be a hell of a lot quicker if we just didn't create the bugs in the first place?”

“Graphical design notations have been with us for a while... their primary value is in communication and understanding. A good diagram can often help communicate ideas about design, particularly when you want to avoid a lot of details. Diagrams can also help you understand either a software system or a business process. As part of a team trying to figure out something, diagrams both help to understand and communicate that understanding throughout a team. Although they aren't, at least yet, a replacement for textual programming languages, they are a helpful assistant... Of these graphical notations, the UML's importance comes from its wide use and standardization within the OO development community.”