- Usually Louis Pasteur is credit for introducing this expression in French (1848). Note, however, that I know a slightly earlier usuage in English, but the context in that case is not very interesting (some ships are dissymmetric). In the same time, Pasteur solved a main problem of chemistry and the new expression is associated with the birth of stereochemistry (3D chemistry).
- The problem was the following: how is it possible that molecules with the same chemical composition and the same geometric shape may have different physical properties, specifically turning the plane of the polarized light to the left or to the right? In his paper, Pasteur suggested that the left-handed molecules and the right-handed molecules are equiavalent in geometry by a mirror reflection, but still these are different physically. Indeed, we cannot move our left hand into the postion of our right hand. A practical problem: a left-handed glove cannot be transformed into a right handed one.
- It is important to note that not all figures have left-handed and right-handed versions. Let us think, for example, about a cube. What are the requirements of having left-right versions. The answer by Pasteur is that some elements of symmetry should be missing. Thus, mirror symmetrc objects have no left-right versions. However, there is no need for asymmetry, the total lack of elements of symmetry: the letters S and Z have two-fold rotational symmetry, but still have two versions. These two letters are often “mirrored” by small children and people with dyslexia also have problem with these. Using Pasteur’s terminology: dissymmetry is needed for having left-handed and right-handed molecules, not asymmetry. Of course, asymmetry can be considered as the extreme case of dissymmetry.
- Later, Pierre Curie adopted the same term into physics (1894). He went so far that made a famour claim: “Dissymmetry makes the phonmenon”. Then Russian crystallographer adopted the expression (Shubnikov and Koptsik). Unfortunately, the term “dissymmetry” was sometimes translated into English as “asymmetry”, eliminating the important difference between the two expression. I also noticed that a book in Japanese translated the French term “dissymmetry” as “antisymmetry”. In fact, I suggested a new Japanese expression to make distinction (“fu-tai-shou”).
- I believe that the concept “dissymmetry” is very useful in aesthetics, too:
- – Symmetry: perfect order,
- – Asymmetry: total chaos,
- – Dissymmetry: its small level may have the aspect of beauty.
- Here we see immediately that we should have (dis)symmetry measures. The topic of symmetry is not any more a yes/no question, but a quantity that should be measured. There are various methods for measuring symmetry.
- Some experimental-aesthetical investigations made clear that we prefer a small level of dissymmetry much better than the perfect symmetry. I was told by a physical anthropologist that not only the very much asymmetric face may hint some mental disorder, but also the perfectly symmetric one.
- A related topic is the often discussed topic of the right-brain / left-brain. In 1989, at the opening of the first congress of ISIS, I suggested to speak about art and science not as”two cultures” (Ch. P. Snow), but as about just one culture, which is a split culture (cf., split brain) with two “hemisphres” (art/humanties and science/technology). Obviously, the two “hemispheres” of culture should cooperate, similarly to the functioning of human brain.
- I am eager to revitalize and popularize the concept dissymmetry not only in science, but also in art.
- My related publications (the papers on “split culture” not listed here):
- Nagy, D. (1984) Szimmetria – aszimmetria – disszimmetria, [Symmetry-asymmetry-dissymmetry, in Hungarian], In: Természettudomány – világnézet – kultúra, Visegrád: ELTE TTK Filózófia Tanszék, 149-152.
- Nagy, D. (1996) (Dis)symmetry measures, Circular of the Society for Science on Form, Japan, 10, No. 3, 16-17.
- Nagy, D. (1997) (Dis)symmetry in art and science: East and West, [Abstract of a plenary talk, in English and Chinese], Abstracts of the Papers of the II East Asian International Semiotic Seminar, [Shanghai, October 19-25, 1997], Shanghai, China: East China Normal University, 95-96. [The full version is also published.]
- Nagy, D. (1998) (Dis)symmetry: Mathematics and design, Euclidean vs. Vitruvian mathematics, In: Barallo, J., ed., Mathematics and Design 98: Proceedings of the Second International Conference, [June 1-4, 1998], San Sebastian: Universidad del Pais Vasco, 17-25. [Paper version of an invited plenary talk].