Geyl was best known as a critic of the British historian
Arnold J. Toynbee, who seemed to maintain that he had discovered "laws" of history that proved how civilisations rise and fall. Geyl often debated Toynbee both on the radio and in print. He accused Toynbee of selective use of evidence to support pre-conceived notions and of ignoring evidence that did not support his thesis. In addition, Geyl considered Toynbee's theory to be simplistic, ignoring the full complexity of the past; he regarded Toynbee's theory of "challenge and response" to explain historical change as too loose and a catch-all definition. Finally, Geyl was opposed to Toynbee's apparent claim that Western civilisation was in terminal decline. Geyl was noted for challenging the then-popular theory that the historical separation of the Dutch and the
Flemings was a result of "natural" causes. Geyl claimed that there was a "
Greater Netherlands" history and that the Dutch and Flemings separated only during the
Eighty Years' War (better known as the Dutch Revolt in the English-speaking world) against Spain in the 16th century. Geyl argued that the revolt failed in the south not because of political, cultural or religious differences, but only because the geography in the north with its lakes, bogs and rivers favoured the rebels and the geography in the south with its flat plains favoured the
Spanish Army. Had it not been for the accident of geography, Flanders would have been part of the
Dutch Republic. Geyl expressed his ideas in a series of articles and in his main work,
De Geschiedenis van de Nederlandse Stam (1930–1959, unfinished). In accordance with his historical ideas, Geyl actively supported the
Flemish movement, though not favouring Dutch-Flemish
irredentism. Geyl's work has been criticised for not taking into account the unifying force of administrative and economic developments after the separation and for sometimes drawing artificial boundaries based on language alone; on the other hand, it has been praised for its refreshing approach to the Dutch Revolt, which was in marked opposition to the then-current nationally oriented, almost finalistic view on Dutch and Belgian history as represented by P.J. Blok and
Henri Pirenne. Geyl was also noted for arguing that the
House of Orange and the Dutch people were often in conflict, especially during the 18th century. Geyl accused
William IV of Orange of using the uprising of the
Doelisten (a group of Amsterdam burgers) against the ruling elite to seize power for himself in 1748. Another
revisionist claim made by Geyl was that the marriage of William of Orange (later stadtholder
Willem II) to
Mary Stuart was the main cause of the
first Anglo-Dutch War in the 17th century.
Napoleon For and Against was an account of how French historians of different ages and views have regarded the French emperor. From Napoleon's time to the present, French historians have presented Napoleon as either a
Corsican adventurer who brought death and destruction to France or as a patriotic Frenchman who brought glory and prosperity. Geyl used his book to advance his view that all historians are influenced by the present when writing history and thus all historical writing is transitory. In Geyl's view, there never can be a definitive account for all ages because every age has a different view of the past. For Geyl the best that historians could do was to critically examine their beliefs and urge their readers to do likewise. Geyl felt that history was a progress of "argument without end", but did not feel that this meant that an "anything goes" interpretation of history was acceptable. ==Death==