"If God had looked into our minds he would not have been able to see there whom we were speaking of." (Part II, p. 217)
A great deal of the Investigations are devoted to the philosophy of mind. Wittgenstein wants to show us that words like "meaning," "understanding," "believing" and so on do not refer to any distinct mental state or process. Further, it is inconceivable that they should, as none of the criteria we use to justify talk about mental phenomena appeal to inner states or processes. Psychologists have a mistaken conception of the mind when they think it is only a matter of experiment and observation in determining what exactly understanding consists of, what meaning consists of, and so on. The mental life we talk about so unquestioningly is very different from the mental life we actually have.