Albrecht von Haller: Commentarius de formatione cordis in ovo incubato

De formatione cordis in ovo incubato was truly the crowning glory of Albrecht von Haller’s embryological studies. In all of Haller’s writings self-criticism and revision were inescapable choices and this work was developed out of a total of 458 «protocols» of observations; it was written in Latin, consigned to print in French, and re-elaborated in Latin in the final version (1767). In addition to the exceptional quantity of material contained in this work, it has one special feature that makes it unique. In this case, the comparison between «private» notes, the unpublished draft and printed versions actually gives us the opportunity of following the itinerary of the author who, at the height of his scientific maturity, suspended judgement on the theory of generation which he then supported (epigenesis), sought confirmation of his new ideas through experimentation, and sensationally overturned his original hypothesis, endorsing the opposing theory (preformism) with his authority plus an enormous mass of corroborating data. This critical edition, which is, up to now, the only one existing for Haller’s works, visualizes the logic and chronology of this path beset with vicissitudes, to determine whether it was the observations or rather ideological considerations that induced Haller to espouse preformism. The basic text used is the 1767 Latin version, which has been collated with the unpublished draft and compared with the French translation. In the first part of the work, in parallel text with the individual protocols, the corresponding private notes have been reproduced, of which the printed text was a thorough re-elaboration. This edition is prefaced with a lengthy historical-critical essay that attempts to violate Haller’s solitude as he worked in his laboratory and to «spy on» his actions and procedures. The aim is to interweave the reasons for the stratification of the text, his choices in scientific writing and in the communication of his results, with the torment of an intellectual torn between extreme experimental honesty, deeply-felt religious beliefs, the coherence of the system and the inflexible impositions of scientific methodology.