Intelligence may have been dropping since Victorian times: https://www.sciencedirect.com/science/article/pii/S0160289613000470 https://www.sciencedirect.com/sci

Intelligence may have been dropping since Victorian times: https://www.sciencedirect.com/science/article/pii/S0160289613000470 https://www.sciencedirect.com/science/article/pii/S016028961...