6 ideas
Watsuji argues that climate is not an external object that acts on us but a way we discover ourselves. When we feel the cold, we are already outside ourselves in the cold, and we respond together by building houses, choosing clothes, and changing customs. On this view, climate is less a cause of culture than the medium through which people come to understand themselves.
Watsuji treats the human being (ningen) as both individual and social, constituted by the relations between people (aidagara) rather than by an isolated self. He holds that these relations are spread across space and land as much as across time. Looking this way turns attention from inner consciousness to shared, located patterns of living.
Watsuji sorts climates into three types and assigns each a human character. Monsoon heat and humidity bring abundance and violent storms, and he says they breed receptive, resigned endurance. Desert scarcity breeds combative, tightly bound tribes that submit to a single transcendent God, while the meadow's mildness breeds calm confidence. The mechanism is overgeneralised: it moves from weather to the temperament of whole peoples with almost no evidence.
Watsuji claims that in Europe's meadow climate, weeds do not overrun the land and weather is rarely violent, so nature seems regular and obedient. He argues that a nature which yields to order encourages people to look for laws, and he treats this as one factor, alongside the historical development he also discusses, in the growth of Western rationalism and science. Even so, the step from landscape to a mode of thought carries most of the argument's weight and rests on little evidence.
Watsuji argues that Japan is monsoon country with two added features: sharp seasonal change and sudden typhoons. He claims these produce a doubled temperament of 'quiet passion' and 'combative resignation', in which feeling swings abruptly and then settles into calm acceptance. This is where the book's reasoning is most openly shaped to flatter a national self-image.
Watsuji points to the Japanese house, where rooms are divided by sliding paper screens with no locks, and reads this as evidence that the family forms one undivided 'betweenness' with little private distance inside it. He carries this household intimacy toward loyalty to the emperor and the state, though he explicitly says that equating family and state is a mistake. The analogy still lends an architectural observation to a nationalist picture, even with that qualification in place.