Mental categories in natural languages

Is the way we conceive of the mind an artefact of the culture in which we happen to live? A recurrent question in the study of languages and cultures concerns the extent to which language and culture shape thought. No one doubts that important conceptual categories are derived from our native tongue but how deep is the impression language makes on thought? Is the way we classify the various phenomena we experience language-and-culture relative in some strong sense? Consider the following thesis: 'But for the language we speak and the culture in which we live we would not conceive of the world in just the way we do'. This is presumably true. However thus stated it is also a very weak claim. For it amounts to little more than the truism above - that many of our conceptual categories are derived from our specific linguistic-cultural context. To be sure, the thesis becomes more interesting once we discover that certain classifications such as those of colour are not the universals we might have expected them to be.