It's not simply a question of images, though.
To grasp these important things, we need not to reason verbally, but rather to look more attentively at what lies before us. “Don’t think, look!” Wittgenstein urges in Philosophical Investigations. Philosophical confusion, he maintained, had its roots not in the relatively superficial thinking expressed by words but in that deeper territory studied by Freud, the pictorial thinking that lies in our unconscious and is expressed only involuntarily in, for example, our dreams, our doodles and in our “Freudian slips”. “A picture held us captive,” Wittgenstein says in the Investigations, and it is, he thinks, his job as a philosopher not to argue for or against the ￼￼truth of this or that proposition but rather to delve deeper and substitute one picture for another. In other words, he conceived it as his task to make us, or at least to enable us, to see things differently.
It is still sometimes hard to reconcile the earlier and later Wittgenstein, although people argue for continuity. Martin Seligman, the positive psychologist, says he later realized Wittgenstein's minute analysis of "puzzles" made him the Darth Vader of philosophy. We have both poison and antidote. I might have to re-read Monk's book again.
Thus, at the heart of Wittgenstein’s philosophy is what he calls “the understanding which consists in ‘seeing connections’ ”. Here “seeing” is meant not metaphorically, but literally. That is why, towards the end of the book, he devotes so much space to a discussion of the phenomenon of seeing ambiguous figures such as the duck-rabbit. When we “change the aspect” under which we look at the picture, seeing it now as a duck, now as a rabbit, what changes? Not the picture, for that stays the same. What changes is not any object but rather the way we look at it; we see it differently, just as we see a face differently when we look at it, first as an expression of happiness and then as an expression of pride.