Interview: MIT Professor Wayne O'Neil, expert on second-language acquisition. It is clear that perfection in the acquisition of a second language after the age of about seven years or so is not possible, except for very rare individuals. [...] The concept ‘ineffability', the idea the some things are beyond expression, between languages has little empirical support. Nor is there any empirical support for the Sapir-Whorf conjecture, that we are conceptually trapped by the language we speak. There is no Iranian mind, Norwegian mind, etc. mind; there are just human minds full of thoughts. If knowledge of language can be said to have a function, then its function is to allow a person full expression of his or her thoughts, whatever these may be and wherever a person's mind may travel.
I think in images and math also. So do others.
Language doesn't define intelligence alone