Reflections on Pascal's Two Types of Esprit in the Light of Certain Current Insights into Brain Physiology

REFLECTIONS ON PASCAL'S TWO TYPES OF ESPRIT IN THE LIGHT OF CERTAIN CURRENT INSIGHTS INTO BRAIN PHYSIOLOGY ARNOLD VAN DEN HOOFF* I wish I could construct canals ivithin my head to promote IIw internal trade between the supplies of my thoughts. But there they lie by hundreds without benefiting each other. [Georg Christoph Lichtenberg (1742— 1 799)] As far as I am aware nobody seems to have yet pointed out a parallelism between views on the human mind expressed by the seventeenthcentury physicist-mathematician-philosopher Blaise Pascal and present insights with respect to a complementary functioning of the two hemispheres of the human brain. The similarity, in my view is too remarkable to be left unnoticed. In one of his Pensées (21), Pascal distinguishes between two types of mind: esprit de geometrie and esprit de finesse. In this essay I shall refer to Jacques Chevalier's classification of the Pensées [1] and to the English translation by J. M. Cohen [2]. Cohen has translated the two phrases, respectively, as the "mathematical mind" and the "intuitive mind." The principles of the esprit de geometrìe are "tangible but far away from ordinary experience ... it is difficult to look in their direction," but once we have discerned them, "our minds must be entirely defective if we draw the wrong conclusions from principles so plain that it is hardly possible to miss them." The principles of the esprit de finesse on the other hand, "rest on common experience; and all eyes can see them" (soni devant les yeux). It seems obvious that Pascal formulated his thoughts tentatively, for in the same pensée (2 1) he states that the principles of the esprit de finesse "are scarcely *Laboratorv of Histology and Cell Biology, University of Amsterdam. Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.© 1985 by The University of Chicago. All rights reserved. 0031-5982/86/2901-04653501.00 164 J Arnold van den Hooff ¦ Current Insights into Brain Physiology visible; we feel them rather than see them (on les sent plutôt qu'on ne les voit), and we have infinite difficulty in conveying this feeling to those who do not feel it for themselves." Apparently· the term "to see" (voir) does not allow for the expression of subtle distinctions between the various modes in which sense perceptions are apprehended. "We cannot give orderly demonstration of the principles of the esprit de finesse as in mathematics since we have not the same mastery of the principles ... to some extent at least, the thing must be seen at once, at a single glance, and not by process of reasoning." (By the way, I wonder whether it would not have been helpful to Pascal if he could have availed himself of the two German terms Goethe applied by preference: sehen and schauen. Schauen to me seems to express rather well what Pascal has tried to convey.) The esprits fins (intuitive minds) are characterized by "their absolute inability to look at the principles of mathematics." Mathematicians (géomètres), on the other hand, are excluded from the esprit de finesse because "they do not see what is before their eyes." In pensée 24 we read: "intuition is the expression ofjudgement, mathematics of intellect." Recent clinical and experimental neurological observations have led to the distinction of two types of complementary perceptual and mental functioning, each dominantly localized in one of the hemispheres. The performances of the so-called dominant (left) hemisphere can be summarized as mathematical-computer-like, analytical of detail and, over time, ideational. They can be verbally and linguistically described, and there is a liaison with consciousness [3]. The "minor (right) hemisphere has no direct liaison to consciousness, is almost nonverbal, synthetic, and holistic. The specialties of the right hemisphere are nonmathematical and nonsequential. They are "largely spatial and imagistic, the kind in which a single picture or mental image is worth a thousand words" [4]. The observation that minor hemispherectomy in a musician has led to a loss oí musical ability whereas the memory of words of songs was retained is suggestive of the localization of musical ability in the minor hemisphere [3]. Clinical evidence points to...