In the southern hemisphere summer of 1848, twenty-three-year-old Thomas Henry Huxley was sailing Australian waters as Assistant Surgeon on HMS Rattlesnake. He was head-over-heels in love with a young woman he had met Down Under, and drifting into the critical skepticism about matters of religion he would later dub "agnosticism." Other than young Henrietta "Nettie" Heathorn, the main thing on his mind was jellyfish, of which he had netted hundreds. As the ship sailed up the Australian coast he worked at sorting out the relationships among his many specimens, and between the jellyfish and other marine organisms.
Huxley's brilliant biographer Adrian Desmond writes: "Nettie, a sensible girl who liked Schiller and penned love poems, must have asked 'Why jellyfish?' And he must have led her self-importantly from these pulsing 'nastinesses' to the great problem of existence, contrasting the tiny truths of creation with the great sandcastle sophistries for which men were willing to die. The tiny truths were real bricks which would build a palatial foundation to Truth. They were stanzas of Nature's great poem; and only by reciting the ultimate sonnet could we gain a rational set of mores and a real meaning to life."
Darwin grand synthesis, that would make sense of Huxley's jellyfish observations, was still more than a decade away, and Huxley would eventually enter the lists and make a name for himself as "Darwin's Bulldog." But here in the South Seas we see him formulating his own important contribution to the human story: The idea that we have something important to learn about human mores and meaning from even the lowliest blob of protoplasm afloat in the sea. He had already decided that eternal truths, if they were to be found, would be discovered in the Book of Nature, not from the hands of Anglican high divines, as a patient accumulation of individually minute observations. The only knowledge worth having was secular, not theological, and "was not to be delegated by episcopal patrons, but seized by plebeian hands." The jellyfish represented common knowledge, by and for the common person.