Lera Boroditsky, of Stanford University, has amassed interesting data on the effects of how we speak of things, such as that people who speak languages that use the same word for a pair of colours need more time to distinguish between them than ones who have a separate word for each – but they can distinguish between them. Mandarin speakers conceptualise time vertically while English speakers conceptualise it horizontally – but each language could use the other metaphor; it has the words for it.