Humboldt-Universität zu Berlin - Philosophy, Science and the Sciences

Mikhail Silian

Mikhail SilianDissertation project

Does our ability to see shapes, or to observe locomotion, depend on our perception of colors? And in what sense does the perception of colors provide the basis for scientific knowledge? In my dissertation project, I reconstruct how Claudius Ptolemy, an Alexandrian polymath who lived in the second century C.E., answered these questions. I focus on Ptolemy’s Optics, the treatise originally written in Greek but only extant in the XIIth century Latin translation. In the second book of the Optics, Ptolemy explains how we perceive such properties of visual objects as figure, size, shape, or opacity. In contrast, in the following books Ptolemy focuses on studying optical images by creating their geometrical models. In this context, it does not seem clear, how Ptolemy’s account of visual properties from the second book prepares the reader for the geometrical exposition of optical laws in the following books. In my project, I will clarify this issue, as well as present my reading of Ptolemy’s more general theory of visual perception.


Mikhail Silian studied at St. Petersburg State University and the University of Leuven. Since 2014 he is working on his dissertation project Claudius Ptolemy on Visual Properties at Humboldt University of Berlin, with Prof. Dr. Markus Asper and Prof. Dr. Dr. Stephen Menn as his supervisors.


2014 M. Silian, “Christoph Helmig. Forms and Concepts [Review]”, in: Vestnik Russkoy hristianskoy gumanitarnoy akademii, Izdatelstvo RHGA, Sankt-Peterburg, Tom 12, Vyipusk 2, 2014, S.342 – 345.
2014 M. Silian, “Tri teorii relyativizma (Three relativistic theories)”, in: Vestnik LGU imeni A.S. Pushkina, No 1, tom 2. Filosofiya Izdatelstvo LGU imeni A.S. Pushkina, Sankt-Peterburg, 2014.
2012 M. Silian, “Rol ponyatiy dunamis teles i dunamis ateles v filosofii Prokla Diadoha” (The Role of “Dunamis Teles” and “Dunamis Ateles” Concepts within the Philosophy of Proclus Diadochus), in: Dnі nauki fіlosofs'kogo fakul'tetu – 2012", Mіzhn. nauk. konf. (2012, Kiїv). Mіzhnarodna naukova konferencіja "Dnі nauki fіlosofs'kogo fakul'tetu – 2012", 18–19 kvіt. 2012 r.: [materіali dopovіdej ta vistupіv], ed. by A. Є. Konvers'kij, Kiev: Vidavnicho-polіgrafіchnij centr "Kiїvs'kij unіversitet", S. 49-51.
2011 M. Silian, “Filosofiya Blazhennogo Avgustina i stanovlenie ponyatiya «intentsionalnost»” (Philosophy of St. Augustine and the Origins of the concept of intentionality), in: Vestnik RHGA, vol. 12, issue 4, St. Petersburg: Izdatelstvo RHGA, S. 250-254.
2011 M. Silian, “K probleme formirovanija koncepcii genad u Prokla Diadoha” (On the Issue of Origins of the Concept of Henad in Proclus Diadoschus), in: Mizhnarodna naukova konferencija “Dni nauki filosofs'kogo fakul'tetu – 2011”, 20-21 kvitnja 2011 roku: materiali dopovidej ta vistupov, vol. 1, Kiev: Vidavnichno-poligrafichnij centr «Kiïvs'kij universitet», S. 54-56.
2009 M. Silian, “Sobyitie i informatsiya (Event and Information)”, in: Filosofiya i zhizn: Tezisyi dokladov i vyistupleniy studencheskoy nauchnoy konferentsii 21 noyabrya 2009 g. v ramkah Dney Peterburgskoy filosofii-2009. St. Petersburg: Sankt-Peterburgskoe filosofskoe obschestvo, S. 37.