Long before fMRI and EEG, the light microscope was the only way to illuminate the world of the infinitely small that exists inside the brain. In the nineteenth-century, pioneering investigators of the central nervous system had to compensate for primitive technology with extraordinary artistic talent. These men produced drawings of their experimental slides in order to preserve the revelations therein. Strange, complex, and utterly gorgeous, these figures are the inspiration for Cajal’s Butterflies of the Soul (2010) by Javier DeFelipe. The book, published by Oxford University Press, contains two-hundred and eighty-two one-of-a-kind images, truly exquisite neuroscientific data.
But this is not merely a picture book; there is an abundance of valuable text. The first part contains a detailed, well-told background and history of neuroscience and technology. Like an art historian, DeFelipe separates the material into three periods: Benedictine, Black, and Colorful. (“Black,” for example, refers to the revolutionary reazione nera, the chemical stain invented by Camilo Golgi that earned him a share, with Cajal, of the Nobel Prize in 1906). I cannot imagine that a traditional textbook could do a better job of presenting this information. The writing is approachable and engaging, and surely enhances the visual experience that follows in the second part. After their introduction, the images become more than aesthetic stimulation; they acquire special meaning because they represent the seeds of early anatomical discovery that grew into the field of modern neuroscience.
Although the book includes the work of ninety-one scientists, Cajal’s Butterflies of the Soul is named for only one: Santiago Ramón y Cajal, the Nobel Prize-winning “father of modern neuroscience” who compared himself to an entomologist and described pyramidal cells (neurons that he himself discovered) as “butterflies of the soul.” Cajal, who said that “only artists are attracted to science,” originally wanted to be an artist. He spent countless hours during his youth drawing natural scenes. In the end he found aesthetic fulfillment in science, and his iconic figures are still used in textbooks. Cajal is one of the greatest examples of a jointly artistic and scientific mind, one that could only have flourished in harmony. (The book’s author, Javier DeFelipe, is a research professor at the Cajal Institute in Madrid).
Cajal’s Butterflies of the Soul, with big, glossy pages and a fancy silver place-holding ribbon, is expensive ($75—$60 on Amazon). But I contend that it is worth the price. I would rather not attempt to translate the unique images into descriptive approximations. I prefer instead to use my words to urge the reader to see for his or herself. To me, the rest of the images found in the book images suggest an epic range of expressive styles; some figures resemble cave drawings, some remind of surrealism. It all amounts to an affirmation of the fundamental beauty of this holy human organ, something to never forget.
These unique works surely belong in a museum. Indeed, that is the opinion of DeFelipe. I was fortunate to be present at a small release event for the book that took place at last year’s Society for Neuroscience conference in Chicago. At the end of his engaging talk, DeFelipe showed slides of an imaginary museum that would display the astounding work we had all just seen through the projector and which appears in the pages of the book. There were even, if I remember correctly, virtual ladies and gentlemen milling about the floor and admiring the featured art. The small conference room was struck, I believe, by the normalcy of the scenario. The message: this science is art. And I will say that I, for one, look forward to the day when I can visit an exhibit in a real museum.