We should note that all of these places of thermal extremes (Finnish saunas, Japanese hot baths, American beaches and mountains) have their opposites close at hand. There are possibly two reasons for having the extremes right next to each other.
The first is physiological: the availability of extremes ensures that we can move from one to the other to maintain a thermal balance.
The second might be termed aesthetic: the experience of each extreme is made more acute by contrast to the other.
Works of art which have great life often have intense contrast within: rough/smooth, solid/void, loud/silent, empty/full. It is the difference between opposites which gives birth to something. Contrast is what often gives other principles their degree of life – the intensity of the boundary, the markedness of the alternating repetition.
Contrast strengthens centers by making each a deeper entity of itself, and thereby giving deeper meaning to both. It is, at its simplest, what allows us to differentiate. But meaningless contrast remains meaningless. It is only when centers are actively, mutually, and meaningfully composed that it acts to deepen the whole.
People mix the terms UI and UX together. UX is tricky because it doesn’t refer to any one thing. Interface design, visual styling, code performance, uptime, and feature set all contribute to the user’s “experience.” Books on UX further complicate matters by including research methods and development methodologies. All of this makes the field confusing for people who want to understand the fundamentals.
That’s why I avoid teaching the term ’UX.’ It means too many things to too many different people. Instead I focus on individual skills. Once you understand the individual skills, you can assemble them into a composite system without blurring them together. For software design, the core skill among all user-facing concerns is user interface design.