Even the weak Sapir-Worf hypothesis is quite tricky to test in practice. It's likely true, but quite hard to prove. Guy Deutscher's excellent book Through the L

Even the weak Sapir-Worf hypothesis is quite tricky to test in practice. It's likely true, but quite hard to prove. Guy Deutscher's excellent book Through the Language Glass documents much of the work that's been done in that area. Mostly, what's amenable to testing is colour perception and absolute direction, more than anything else.