Topics Knowledge

Question This problem has been nagging me forever. If "objective reality" is simply a consensus between experiencing subjects, then on what grounds can we claim to know or understand anything? How can we be so sure that - for example - our scientific knowledge is accurate? Is it just because there is greater consensus in established academic fields like physics or biology? What about the people our society labels as insane? Is their interpretation of reality wrong simply because there is less consensus about it?

Accepted:
July 5, 2008

Comments

The difficulty here is with the idea that "objective reality" is a matter of consensus. I've heard that said often enough, though virtually never by a philosopher or a scientist. I must confess that I've never really understood what makes the idea seem plausible or attractive.

Whatever the details, it seems reasonable to think that the world is the way it is whatever I think of the matter. The universe existed for eons in sublime indifference to the fact that we weren't around to have opinions about it, and after we mess things up and end our species' sojourn in the world, things will once again go on without somehow having gotten vague, fuzzy or unreal due to our absence. Gaseous gab about "consensual reality" is perennially fashionable in some circles, but the fact that some people are inclined to talk this way doesn't mean that it has a lot going for it.

Of course, whether what we think about the world gets things right is another question. The plausible common-sense answer is that we're likely right about some things and wrong about others. It seems particularly odd to worry about whether we're right in thinking that there are trees, plants, stars and ugly lawn ornaments. It's not odd at all to wonder whether we really know if there are such things as Higgs bosons.

So you're quite right: if we really took seriously the idea that "objective reality" is a mere matter of consensus, we'd have a hard time making sense of knowledge. This is one more reason for not taking the idea seriously in the first place: it's self-undermining. But then, as many people have noted, it's more directly incoherent. It makes a putatively objective claim about the nature of reality (that it's somehow a product of consensus), and the claim itself is very far from being part of any shared consensus. The "consensus" acount of "objective reality", if true, is false by its own standards. Not a good recommendation for a philosophical claim.