1900 was a remarkable year for science. Several ground-breaking events took place, in physics, biology and psychology. Planck introduced the quantum concept, the work of Mendel was rediscovered, and Sigmund Freud published The Interpretation of Dreams . These events heralded the emergence of completely new areas of inquiry, all of which greatly affected the intellectual landscape of the 20 th century, namely quantum physics, genetics and psychoanalysis. What do these developments have in common? Can we discern a family likeness, a (...) basic affinity between them, so that we can use the one to deepen our understanding of the other? One common denominator is that they open up realms of inquiry that are significantly different from the world of everyday experience, namely the realm of elementary particles, of genes and genomes, and of the unconscious. But to what extent can we meaningfully argue, for instance, that the genome is the biological unconscious, and the unconscious the psychic genome? To address these questions, I will build on the work of two key intellectual figures who have explored the affinities of these developments in depth, namely Erwin Schrödinger (a quantum physicist and avid reader of Schopenhauer who initiated molecular biology) and Jacques Lacan (who reframed the specificity of psychoanalysis with the help of 20 th century science: the era of structural linguistics, but also of quantum physics, molecular biology, bioinformatics and DNA). (shrink)