9 ;;Quote: even simplified scripting languages need general-purpose control structures and variables

11 ;;Quote: user interface management systems were not successful; need low-level control; have standard interface elements

11 ;;Quote: it is easy to express sequencing in formal UI systems; does not work for direct-manipulation user interfaces

12 ;;Quote: formal systems have a high threshold for using them; e.g., define a grammar to express sequencing in dialogs

12 ;;Quote: constraint solvers can be unpredictable, difficult to debug, and difficult to master

12+;;Quote: constraint solvers are useful for graphical layout with springs and struts

13 ;;Quote: automatic and model-based techniques for user interfaces had unpredictable heuristics and generated poor interfaces

15 ;;Quote: off-the-shelf computers are as good a researchers' computers; can't buy high-performance computers to study what will be available in five to ten years

15 ;;Quote: high performance computers enable cinematic user interfaces with smooth transitions, animation, and sound effects

20 ;;Quote: spreadsheets are successful because of end-user programming; rarely available in other applications or requires conventional programming

20 ;;Quote: spreadsheet formulas are like constraints; fits business mental model, but not programmer's mental model