Partly I explained to Lucas that I think this is because Spanish speakers are continuously brooding, so they have no contrast and therefore haven't formed the concept.
Anyway here is a footnote I wrote to explain the idea. Any thoughts?
*The english poetic term “brooding” uses the root idea of cultivating a nest, of gestating or incubating something, as with sitting upon a brood of eggs or newborns to enable them to grow in a warm and protected way, but in the emotional sense particularly congealing one’s diffuse, searching melancholy into a more coherent and resolved form of pain. Thus the biological analogy of slowly helping your babies carries over to mean a mental activity of dwelling upon your shadowy and mysterious threads of hurt, gathering and forming into some living synthesis.