. . . although these my principles make appearances of the representations of the senses, they are so far from turning the truth of experience into mere illusion, that they are rather the only means of preventing the transcendental illusion, by which metaphysics has hitherto been deceived, leading to the childish endeavor of catching at soap-bubbles, because appearances, which are mere representations, were taken for things in themselves.
— Immanuel Kant, Prolegomena to Any Future Metaphysics (1783), Main Transcendental Question, First Part, Note III.
It can only be our familiarity with soap-bubbles from our earliest recollections, causing us to accept their existence as a matter of course, that prevents most of us from being seriously puzzled as to why they can be blown at all. And yet it is far more difficult to realize that such things ought to be possible than it is to understand anything that I have put before you as to their actions or their form.
— Sir Charles Vernon Boys, Soap Bubbles (1890).
But while I have always known exactly and with premeditation what I wished to obtain of my senses, the same is not true of my sentiments, which are light and fragile as soap-bubbles.
— Salvador Dali, The Secret Life of Salvador Dali (1942).
Once you decide to give credence only to those things in Lacan that are based on reasoning from evidence, as those terms are usually understood, what remains is little more than the residue of soap scum after the bursting of a glistening bubble. If I were to use Lacan's method I would write that soap bubble metaphor in more abstruse terms, stretch it for endless pages of waffle, and pretend that it was an argument or proof rather than merely a figure of speech.
— 'Laon', review of Alan Sokal and Jean Bricmont, Fashionable Nonsense, at amazon.com.