Guard

As I see it, our senses give us absolute, immutable truth. Everything else is conclusion drawn from that. If those conclusions are drawn logically, they are true. When we perceive things that "contradict" those conclusions, we alter our conclusions accordingly. But does it mean that the conclusions we drew earlier from what we had perceived were wrong? I don't think so. Consider the old hypo of swans. All the swans you see are white, and you conclude that all swans are white. Then you see a black one. Is the black one really even a swan? The concept "swan" had been created for existents of a certain type that were white. So, why should we even call a similar bird that is black a swan? They are different. We do so because it is cognitively efficient to. And the fact that it is cognitively efficient to call the black one a swan in no way makes our prior conclusion wrong. It just means that we are not omniscient and did not know there were similar entities that were black. One can make a similar observation about blood types by regarding incompatable blood as another type altogether BECAUSE it is incompatable. The whole idea behind concept formation is to GRASP what is real. To reduce our enormous sensory input to something we can hold in our minds. No one claims it is a technique for achieving omniscience. Until someone observes that Type A blood does not always match, there is no reason for assuming that it doesn't. In fact, it would be irrational to do so. Acceptance of beliefs without evidence is mysticism. So I don't see a big problem--just people arguing about how symbols like "truth" should be used. And failing to appreciate that concept formation is a way of organizing that which we perceive. Peikoff was responding to attacks on man's conceptual faculty by people who claim that the growth of knowledge implies skepticism.