Even if we ignore the 'non-theoretical' knowledge which we acquire through experience (such as the knowledge of what something tastes like) and concentrate on theoretical knowledge, there is no good reason to think that physics can literally give the theory of everything. Here I want to be really pedantic. Although everything may be subject to physical law, not everything can be explained or described in physical terms. Physics has literally nothing to say about society, morality and the mind, for example - but of course these are parts of 'everything'.