[4] In 1846, he left Ukraine for Paris, where he became associated with the political and intellectual circles of Prince Adam Czartoryski and published in the "Trzeci Maj" journal.

[11] Duchiński was born in Ukrainian lands, and spent much of his life in Kyiv, with which he was deeply connected; he even used the nickname Kijowianin (Kyivianin).

[12] In Duchiński's writing, the thesis of the non-Slavic anthropological origin of the Russians occupied a prominent place as a kind of idee fixe.

Duchiński rejected the division of peoples into large groups in terms of language, and postulated the use of anthropological features.

The Turans, on the other hand, which he included the Turks, Finns and Mongols, had no love of the land, were passive, fanatical, organised in a military way, and the position of women in their societies was low.

According to Duchiński, peoples of Turan origin, although seemingly leading a civilised, sedentary lifestyle today, nevertheless retained the tendencies of the nomads of old.

[15] Duchiński's theory was deeply rooted in the tradition of Polish historiosophical thought, in which the desire to make Europe realize that Russia was not only fundamentally different from it in terms of civilization, but even hostile, was a key element.

French historian Marlène Laruelle lists among the researchers who adopted the 'Turan' thesis: Henri Martin, Albert Reville, Auguste Viquesnel [fr], Charlier de Steinbach, Casimir Delamarre [fr], Édouard Talbot, Emmanuel Henri Victurnien de Noailles, Élias Regnault and others.

[19] Henri Martin was previously convinced of the Slavic nature of the Russians, although he changed his view after the January Uprising and under influence of Duchiński.

Duchiński was unable to accept this view, which he expressed at a meeting of the Geographical Society held on 19 April 1872, of which Quatrefages was also a member.

Duchiński, however, accepted Quatrefages' main assumptions and assessed that Russian Pan-Slavism and Prussian Pan-Germanism were nothing but a tool legitimizing ruthless conquest.

The first group certainly included Galician Stefan Buszczyński [pl], who wrote several works in Polish and German in which he enthusiastically promoted Duchiński's theses.

[25] Duchiński's works were particularly popular before the January Uprising, when they could reach the country more easily, and promoted the unity of fate of the peoples of Poland, Ruthenia and Lithuania, which became the basis of the revolutionary movement.

[29] Jan Baudouin de Courtenay's criticism of the use of science in promoting political views was similar, equating Duchiński's work with that of Russian Slavophiles.

Thesis about the lack of common ancestry between Ukrainians, who were living in Austrian Eastern Galicia, and Russians was well received in Austria; its reception can be found in the works of Hermann Ignaz Bidermann [de], among others.

[31] On the other hand, German geographer Johann-Heinrich Schnitzler summed up Duchiński's ideas simply as justification of Polish claims towards Ruthenia.