Phil Elmore: Individual Authoring Services

On the Validity of the Senses
by Phil Elmore

Are your flawed senses a valid source of information about the world in which you live?

While everyone's senses can indeed be fooled, one can compensate for this by applying logic to the data perceived. The senses are "necessarily valid" -- because any attempt to discredit the data perceived through them relies on other sensory data perceived through them. Thus, the senses must be used to discredit the senses -- and those who seek to claim they are not valid are making the tacit admission that they are.

To examine the issue further, how would we determine that given data is flawed without using our senses? And how do we come to the conclusion that sensory data, in a general sense, can be flawed without basing that conclusion on previous comparisons of sensory data? It's a trap from which no one can escape: any attempt to question the validity of the senses ultimately comes back to the use of the senses in evaluating something.

We can prove, beyond any reasonable measure of doubt, that certain things are true under certain conditions. Certain actions, taken in the same context, will yield the same results under those same conditions. Here on earth, enough heat applied to distilled water will boil that water every time at normal atmospheric pressure. Charcoal, sulfur, and saltpeter combined in the proper ratio and prepared according to certain guidelines are explosive, every time. Decapitation will always result in the death of a human being whose physiology conforms to what the medical establishment considers "average."

The universe really is knowable. The fallibility or limitations of the senses do not mean that we are left to wander through a universe whose nature is ultimately inaccessible to us. (At least, I don't believe so.)

If we adopt such a pervasive agnosticism, we can never be certain of anything -- that is, if we insist on viewing all pieces of knowledge as contextless absolutes. Certainty, however, as Leonard Peikoff explains in his Objectivism: The Philosophy of Ayn Rand, is contextual -- and provided we define the context in which we ascertain our knowledge, we can make statements of fact with confidence. It is this contextual certainty that makes advancements in knowledge possible.

Recognizing that certainty is contextual is the key to ascertaining what absolute truth is within that context. New information does not threaten certainty. Instead, it augments and amplifies our knowledge. And information that appears to contradict what we already know simply helps us learn more based on our previous conclusions.

To say, for example, "I can't be certain that the Internet doesn't actually exist" is fairly self-defeating. It takes no superhuman or omnipotent cognition to know that computers exist, that this site exists, that e-mail can be sent to others who will respond, and who will confirm in person that they sent that mail. Our senses are fallible, yes -- but not to such an extraordinary degree that the external world and everything in it is a gigantic illusion.