Wil asked:
Please tell me, are objectivity, rationality and universality necessary requirements for all philosophical truths? Are they even possible?
Answer by Massimo Pigliucci
Let’s start from the very idea of philosophical truths. I’m not sure philosophy is in the business of discovering truths in the first place. Certainly not in the sense of discovering things about the natural world or human behavior – we’ve got the natural and social sciences for those tasks already, and they are doing a pretty good job of it.
Philosophy may rather be thought to be in the business of discovering, say, metaphysical or ethical truths, and certainly a number of philosophers would say that this is indeed the case. But I’m skeptical. I don’t think there are objective moral truths “out there,” and I think that morality is a human invention. This doesn’t mean it is arbitrary (after all, its purpose is to regulate human social interactions in a way that is fair and conducive to individual flourishing), and it doesn’t mean that moral philosophy can be reduced to social science (facts about human nature are relevant to ethical reasoning, but they under-determine it, meaning that there are multiple solutions to moral dilemma given certain facts on the ground).
As for metaphysics, its usefulness, I think, lies in clarifying concepts like personal identity and time (see here, for instance), say, and also in producing a coherent picture of how the sciences (fundamental physics, biology, economics, and so on) describe the world. But simply thinking about the way the universe is made isn’t going to reveal any new truths about it – again, that seems to be the job of science at this point.
So, all in all I see the tasks of philosophy as clarifying concepts, exploring their logical consequences, building and examining arguments about ethics and metaphysics, and even analyzing the warrant of scientific claims (that would be philosophy of science). But I don’t think it is useful to construe any of the above as seeking “truths.”
We can now go back to your actual questions, beginning with universality. I doubt it is necessary for philosophical inquiry. While certain areas of philosophy do concern themselves with universal statements (e.g., modus ponens in logic is valid regardless of specific arguments in which it is deployed), many others don’t. Take political philosophy, for instance. When, say, John Rawls wrote his book on how to construct a just society he understood that this is a human concern, and that our concept of justice may or may not apply to other sentient species, or in other places of the galaxy. Indeed, I would argue that unless we are talking about a specific type of social biological organisms endowed with self-consciousness, certain goals and desires, the very concept of justice makes no sense. (Can you be just or unjust toward a rock? An amoeba?) So clearly justice, a fundamentally philosophical concept, is not universal.
I’m going to address objectivity next. Mounting research in social science, as well as scholarship in philosophy of science, seem to agree that objectivity is only an ideal goal, which can be approximated by groups, but which is not a characteristic of individuals. Consider, for instance, science itself, the paragon of an objective human activity. It is pretty obvious from the psychology and sociology of science that individual scientists are actually no more objective than most people. They care about their theories, which means that they are (at the least unconsciously) partial to them; and they adopt (and sometimes vehemently defend) specific points of view about all sorts of things, just like the rest of us. However, the scientific enterprise as a whole approaches a high degree of objectivity because science is a social activity that puts a high premium on truth and verifiability, and where young scientists have huge career incentives in showing that a previously held notion is in fact false. For a more detailed treatment of this approach to objectivity in science, see Ronald Giere’s book,Scientific Perspectivism, or Helen Longino’s The Social Dimensions of Scientific Knowledge.
Finally, rationality. Yes, it seems to me that rationality is required for philosophical discourse. After all, one can define philosophy as a type of rational inquiry, similar to science, mathematics and logic itself. But of course there are different conceptions of rationality, and there is certainly no guarantee that individual philosophers are as rational as one might hope.
With respect to the first issue, for instance, recent research in logic has suggested that there are ways to rigorously account for apparent contradictions and logical paradoxes, ways that are not compatible with standard approaches to logic and rationality. For instance, my CUNY colleague Graham Priest has written about how so-called paraconsistent logic may help us make sense of seemingly contradictory statements from the Buddhist tradition. I’m not sure that I agree with Graham about Buddhism, or in fact even that I buy wholesale into the idea of paraconsistent logic, but that goes to show you that there is (reasonable) disagreement about what counts as rationality – to a point (there is quite a lot that logicians agree on).
Concerning the second issue, the rationality of individual philosophers, I think training in philosophy certainly does refine one’s skills in logic and rational argument – indeed, that may be the chief reason to major in philosophy, or at the least to take philosophy courses. But, ultimately, what brings about rationality in philosophical discourse is similar to what allows for quasi-objectivity in scientific discourse: philosophy is a social enterprise, and you can bet that as soon as a philosopher says something that is not quite rationally defensible a number of other philosophers will jump on it with gusto and tear the poor (argument, not the philosopher) apart. And that’s the fun of actually doing philosophy.
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