"It is human life. We are blown upon the world; we float buoyantly upon the summer air a little while, complacently showing off our grace of form and our dainty iridescent colors; then we vanish with a little puff, leaving nothing behind but a memory - and sometimes not even that. I suppose that at those solemn times when we wake in the deeps of the night and reflect, there is not one of us who is not willing to confess that he is really only a soap-bubble, and as little worth the making."

Source: Mark Twain (2010). “Mark Twain's Own Autobiography: The Chapters from the North American Review”, p.152, Univ of Wisconsin Press