“‘There are two types of popularisers,’ he wrote for a broad scientific audience in 1929. The first ‘feigns sympathy with the less educated’, but takes a condescending tone and ‘grows cranky’ without the ‘crutch’ of ‘jargon and ‘mathematical formulas’. The second takes ‘pleasure and pride’ in letting go of those crutches and succeeds in raising ‘the reader and himself into a more general sphere that lies above that of technical expertise’. If the first type of populariser was arrogant and paternalistic, the second displayed humility and respect for the non-scientist.”