Grey. It makes no statement whatever; it evokes neither feelings nor associations: it is really neither visible nor invisible. Its inconspicuousness gives it the capacity to mediate, to make visible, in a positively illusionistic way, like a photograph. It has the capacity that no other colour has, to make 'nothing' visible.
Painting is the making of an analogy for something non-visual and incomprehensible - giving it form and bringing it within reach. And that is why good paintings are incomprehensible. Creating the incomprehensible has absolutely nothing to do with turning out any old bunkum, because bunkum is always comprehensible.
I am thankful that the church exists, thankful that it has done such great things, giving us laws, for instance - 'thou shalt' and 'thou shalt not', and established Goodness and Evil. That's what all religions do, and as soon as we try to replace them, worldly religions like fascism and communism take over.