In A Brief History of Everything, Ken Wilber posits that reality consists not only of "surfaces that can be measured" - the realm of the sciences - but also "depths that must be interpreted". The realms of the arts and ethics.
If this model is even vaguely correct, we can measure heads and brains all we want, as well as the EM fields surrounding them, and even aspects of cognition. But none of that will ever allow a psychologist to tell someone how they feel, rather than having to ask.
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