Literally "mountains and valleys in the chest"; refers to having a well-thought-out plan or a clear vision for how to handle a situation before acting, originally used to describe a painter's preconceived mental preparation of a landscape.

to enjoy oneself in nature's embrace; to be immersed in the beauty of hills and valleys without being burdened by worldly matters

to be circumspect and astute; to possess a grand vision or a well-thought-out plan in one's mind