4.023 Reality must be fixed by a proposition except for a yes or a no.

Therefore it must describe reality completely.

A proposition is a description of a state of affairs.

As the description of an object goes by its external properties, so a proposition describes reality according to its internal properties.

A proposition constructs a world with the help of a logical scaffolding and therefore one can actually see in the proposition all the logical features of reality if it is true. One can draw conclusions from a false proposition.

So propositions must be quite definite or determinate about something (not the whole of reality, presumably, although maybe that) and not at all vague. A proposition describes the internal properties of a state of affairs. Why? And what are these? If internal properties are logical properties, then do propositions describe these? Presumably. And so a true proposition will describe the logic of a part of the world, of a state of affairs. Since it shows its sense, one will be able to see from it what this logic is. If the proposition is false one will have to think a bit, perhaps just by affixing a mental “not” to the picture presented by the proposition.