Is the Irish climate a blessing in disguise?

If you tire of the grey chill of July, I offer you this cold comfort from the Irish summer. According to traditional theories about the relationship between climate and civilisation, we live in the perfect climate to attain the highest levels of civilisation. Forget suntans: the cool damp has brought us literature and science.

The idea that climate shapes society is old. An influential formulation of the theory was put forward during the Enlightenment by the French philosopher Montesquieu (1689-1755). For him, climate determined the qualities of governments. He suggested that hot climates influenced the bodies and minds of the people who lived in them, making them weak and fearful. Weak and fearful people were vulnerable to despotism, unlike the courageous and vigorous people of colder climates.

As European nations such as France grabbed more and more territory in the tropical regions of the world, many worried about the future of European settlers in those territories. They anticipated dissipation, disease and death.

Such theories, in various guises, have proven extremely durable. In 20th-century Ireland they were closely tied to ideas about the Celtic race and about emigration. As Gerald McCarthy declared in the Irish Review in 1911: "The best country for Irish men and women is Ireland itself." McCarthy breezily claimed that Irish migrants to Australia and Africa would never prosper, nor would those alighting in North America outside of Alaska, Washington state and British Columbia. Hot climates were debilitating to those raised for generations in a cold climate: "It inflames the nerves and causes abnormal muscular activity, like a bear dancing upon a hot stone." Fair-skinned people could never acclimatise to places where summer temperatures averaged more than 20 degrees. Going by this theory, a long holiday in the Canaries risks much more than sunburn.

Austin O'Malley, writing in the journal Studies in 1916, also warned Irish migrants of the dangers to their health and to the Celtic race of thoughtless resettlement. Although O'Malley described climate as embracing a wide swathe of elements, he too focused on temperature. According to O'Malley, the best temperatures for physical labour and mental labour were about 15.5 degrees and 3.3 degrees respectively.

“If the weather is hot and humid, man is depressed; if it is cold and humid he works better than when the air is cold and dry,” he wrote. In Ireland, thanks to the cold humidity, we can be productive all summer long. Far from a blessing, “The American sunlight is the chief obstacle to the development of the European in the United States.”

O’Malley, like McCarthy and many others, believed that each race was suited to a particular climatic region of the world. Those areas of the globe to which we all flee in search of heat and sunlight were, O’Malley claimed, populated with “the inferior races of men”. His general advice was that Europeans ought to stick to parts of the globe with the same climate as the place they came from. Norwegians should not move to Texas and the Irish should avoid Louisiana.

If you have tut-tutted your way through this article thinking that we have come a long way from these racialist views of the climate, think again. Trawl the internet for stories about climate change and you are bound to discover alarmist headlines suggesting that a rise in temperature has already led to increased violence and will cause political turmoil in future.

Of course, rises in temperature might indeed produce catastrophe by undermining agricultural systems and making extreme weather events more frequent. However, there is a lurking presumption about heat that bears a striking similarity to the ideas of O'Malley and McCarthy. As Prof David Livingstone of Queen's University Belfast has pointed out, linking climate change to increased violence is a current trend with a long pedigree.

Most of the predications have to do with a rise in temperature. One wonders if the predictions of social dissolution would be the same if the climate change forecast called for a significant fall in temperature.

• Juliana Adelman lectures in history at St Patrick's College, Drumcondra