Email should be presented one message at a time by default. This is about the in box. The message list is a special purpose function that should activate only when requested.
Define content. An email message is a unit. The screen and window are units. A message is a content unit. Screens and windows are display units. Displaying a message merges a content unit with a display unit. Units can be assembled in strings, activating the next and previous functions. This simply requires stringing functions. If the units are content units, a string of units is a content string.
Define window. A window floats on a screen. A window can also float in a window. Multiple windows can float on one screen or in one window. This distinction allows for the association of windows and content strings. Each window has a content layer, and one content unit can display on that layer. If that unit is strung then the window's string traversing functions can display the next and previous units. Next and previous replace the current unit with the new unit. Other windows in the window float above the content layer.
We need to define these terms so that we can describe things efficiently. Screens and windows are similar things, but we are calling one screen and one a window to differentiate between them. Windows act as screens, and screens can act as windows, if several of them are arrayed together. A screen, however, does not need to be displayed on a screen to function. A window does need to be displayed on a screen to exist. This is what differentiates a window from a screen in our terminology.
I could go on in this way for a very long time without accomplishing much. The existence of a thing depends on context. Without a context the thing cannot exist. A unit of content can be displayed on a screen. It would be displayed on a content layer, which is an abstraction that the screen displays. Above it can be floated a window, which is another abstraction that the screen would display. That window could display a unit of content, on a content layer that the window displays, and a window that the window displays could float above that, and so on ad infinitum. Displaying something on a screen merges that thing, which is an abstraction, with the screen, which is a physical object. Displaying something in a window merges that thing, which is an abstraction, with the window, which is also an abstraction. This uncovers a unifying concern, the display function, which merges an abstraction with either another abstraction or with a physical object, keeping in mind that the display, which is the object with which the object which is displayed merges, requires context to exist. The screen exists in the context of matter, so this context is defined by the screen's existence. An abstraction which displays an abstraction, however, must be defined, relative to a context, and if that context is an abstraction, it must be defined, and ultimately one of these contextual abstractions must be defined relative to something which need not be defined, that is, a screen. This procedure merges the abstract and the material. The process is called programming.
Programming is a language function. The programmer combines symbols into functional articulations. In order to function, however, a functional articulation requires a listener. In a sense, the listener is a screen, or some equivalent inert object, but, given that these are inert objects, the listener is in fact what we call a machine: a computer. As programmers, we must somehow communicate our code to machines. This is where I am at something of an impasse.
Keeping in mind that my present topic is context, the machines with which I wish to communicate, which control screens I would like to program, are controlled by people. Ultimately, if I want to program those screens just the way I want to program them I will need to communicate with those people. This isn't, as it may seem, a completely straightforward equation, but it is an equation. Here it gets kind of interesting. The people who control these machines are offering me access to their machines if I follow certain procedures, but some of those procedures are objectionable to me. Still, these people are offering me certain kinds of access to their machines via procedures which I do not object to, or which, at any rate, I can accommodate. And there exists the possibility that I can communicate with these people via these limited channels. It is, however, quite complicated.
How sweet!