It is not sufficient that two phenomena exist at the same time to conclude that one is the cause of the other.
Complete Works volume I, page 17 (in French)
Letter dated January the 8th, 1925
It is about the economic success of Great Britain at the time that Frédéric Bastiat expresses this truth that is often repeated through the aphorism: “correlation does not imply causation”. The protectionism was so important that French governments would dream about the amount of taxes collected there (a billion) while being convinced that it was thanks to them that the country was so prosperous (the industrial revolution had started there ahead of starting in France).
What is unfortunate is that one hears such a fallacious argument nowadays still. Some look at the US prosperity at the end of the 19th century and attribute it to the high tariffs at the time. Others look at the success of China since 1980 despite the heavy hand of the State and attribute the former to the latter (which is obviously idiotic – the hand of the State was even heavier before 1980 – correlation does not imply causation but its absence proves the lack of causation). All this to justify a backward move towards protectionism across the world that does not bode well for the coming years and/or decades.
In any case, today’s quote is of a much broader reach than the theme to which it refers in the letter to Félix Coudroy and will be invoked again numerous times in the decades and centuries to come.