Dan North:

The five CUPID properties are:

• Composable: plays well with others
• Unix philosophy: does one thing well
• Predictable: does what you expect
• Idiomatic: feels natural
• Domain-based: the solution domain models the problem domain in language and structure

Also this belter from Martin Fowler.

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