HOW?
Definition
The word how is an adverb. When used as a question, it has more potential for diversity than any of the other quintessential questions. In what way? enquires about modality. By what means? asks about methodology. In what condition? questions the state of being. To what degree? concerns the extent of the situation. Then there are indirect or dependent questions: how many? (what magnitude); however? (nevertheless). Hence, the parameter how runs from means to cause.
Purpose
The intention of this question? Despite the fact that intellectuals often disparage this question, it may cover more of the concerns of average people than all of the other questions. People are concerned about the way the world works, and the manner in which they or others behave. To some extent, the shift of priority from the other questions to this one is a hallmark of the modern age – it grounds science & technology.
Explication
There is a very good reason for the shift from why to how in the modern world. It is epitomized by a cautionary tale from industrial engineering: when someone comes up with a better designed car engine, the only way a manufacturer will agree to evaluate it is if a working model is submitted – any such claims must be substantiated with proof of HOW the thing works. That has eliminated any need to test perpetual-motion machines.
Implication
How something works (animate or inanimate) can be covered with either a description or an explanation. These two aspects do not necessarily coincide. It is possible to describe the workings of something (the flight of a bumble bee) without being able to explain it. It is also possible to explain something (the conditions that will lead to political unrest) without being able to describe how that eventuality will actually occur. How is deep too!
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