in this Cartesian meditation, supported by the demonstration of the possibility of tracing the indistinct variety of forms through analytical geometry to a numerical, algebraic law, a new conception of the perspective-mimesis of reality obviously takes hold. Mimesis-simulation that tends to understand, to explain the laws underlying the apparent diversity of reality. The cultural environment of the least, profound connoisseurs of the Cartesian doctrine develops some research sectors through which the analysis of nature that leads to knowledge of its laws is being carried out. Julien33 writes:
Perhaps it is possible to confirm and expand this vision by giving a picture that shows the role of the Minims as the most fervent spreaders of the culture that matured under the impulse of Descartes (and of Galileo in a practical sense, undoubtedly less philosophical than the Cartesian method) and of optics studies in particular as one of the sectors in which the sacred and the exact can be reconciled34.
A scroll was found placed by Niceron (the first creator and designer of the anamorphosis in the Trinity convent) on the tree to the left of San Giovanni, bearing a motto whose meaning must be patiently studied: Citra Dolum Fallimur. The phrase uses a very ancient juridical term, used at least by the Justinian code: citra dolum which we can literally render “On this side of fraud” that is, as commonly translated in jurisprudence, “without fraud” or, in full, “without ‘intent to defraud ». The meaning of the motto is therefore “without fraud we are deceived”; we obviously refer to perspective and its property of deceiving (the eye) without malicious intent. However, Niceron’s is not just a learned and creative reference to the deceptive viewpoint but a quotation: the sentence is in fact taken from the cartouche on the title page of the treatise by Guidobaldo del Monte Perspectivae libri sex35. Fundamental quotation, we can say, since the treatise (from 1600) is the first to be attempted in the rigorous scientific demonstration of the principles of perspective, going beyond the exclusivity of the empirical method used until then. No longer just the graphic construction but laws (hence perhaps the use of legal terminology in the motto) geometric mathematics: a treatise that could not leave Niceron, Cartesian and profound student of optics indifferent. Within these considerations, the study and theoretical elaboration on anamorphoses, deformations of reality according to precise rules, is perhaps more easily explained; rules that allow you to read the truth even where it seems impossible or that show the importance of the correct point of view from which to observe the forms.
Guidobaldo’s work is cited by Niceron, along with others on the subject, already in the preface of the 1638 La Perspective curieuse; in all French editions it is defined as abstract and speculative, of very difficult practical application. In Thaumaturgus opticus it is defined only abstract, again underlining the difficulty of application. So why pay homage to Guidobaldo’s title page in the most important of practical applications?
It can be proposed, by way of non-demonstrable suggestion, that in the preface Niceron was prudently pro-ecclesiastical (in the counter-reformist climate the mathematical statements could be used without consequences only for pure speculation and not to explain reality): perhaps he tries to help draw an image of the environments close to Galileo as purely elucubrative, without practical application value (Galileo had first obtained the imprimatur from Urban VIII for his Discourses, declaring that the use of Copernican theories was exclusively speculative). We recall that Guidobaldo del Monte was the brother of the cardinal protector of Caravaggio and of Galilei himself. Fraternal friend of the Pisan scientist (with whom he had exchanged many scientific considerations on mechanics and fortifications), he had supported and promoted his appointment as professor in Pisa and then in Padua. Perhaps a subtle position was that of Niceron who, while keeping his distance on the printed work, had “lined up” in Rome, in a practical application, for the use (dangerous for ecclesiastical hierarchies) of scientific rigor in the analysis of reality.