What is the problem posed by the relationship of subjectivity to objectivity?
The main problem posed by Nagel’s formulation of subjectivity and objectivity is that it seems, like Heisenberg’s uncertainty principle (and to a lesser degree Einstein’s theories of relativity) to violate the law of non-contradiction. Imagine, for example, that Theaetetus says the it is hot out and Socrates says that it is cold. From a subjective point of view, both are correctly describing, not some external state of reality, but rather their own perceptions. Reframed as “Socrates feels cold and Theaetetus hot” we do not have a logical problem. Nor would either of the statements contradict the objective “the thermometer measures 17 degrees Celsius”. Against which standard would we deduce disordered subjective judgement (Theaetetus, recently wounded in the Peloponnesian wars, has a fever.)? How would we decide how to set the thermostat in a house with many people? Why is the point of view of a machine somehow not just a mechanical subjectivity? Where do we draw the borders between objective and subjective? And how do we adjudicate among multiple subjectivities?