Facts and Perception
There is, of course, a whole world that exists in time and space independently of our minds and perceptions. Things that have extension through space we call objects. Alterations in those objects we call events. These objects and events together are what we typically call facts. The world of facts has real existence whether we perceive it or not, and in that sense it can rightly be called objective.
In principle every event and object is accessible, either immediately to our senses or else through the extension of our senses through instrumentation and other media. We can observe distant galaxies through telescopes, minuscule amoebae through microscopes, speeding electrons in cloud chambers, and so forth. The sheer number of facts that we could observe in any instant is so incalculable that, for our purposes, it might as well be infinite.
Most of these facts, however, escape our notice entirely. Even now you are sensing facts of which you are unaware. Perhaps you have failed to notice the sound of the air moving through the ductwork around you. Perhaps you have overlooked the texture of the ceiling or the intricacies of the pattern in the carpet. Almost certainly you are unaware of the weight of your clothing upon your body. The moment I mention such things, you notice them instantly, but until I did they were completely outside your consciousness. At any given time, we are taking account only of the tiniest proportion of the facts that are available to us, even when those facts are actually stimulating our senses.
The facts that we do sense often turn out to be different than their appearances. You are now reading what you perceive to be words on a computer screen, and you perceive the individual letters of which those words are composed. If you were to examine the characters more closely, however, you would discover individual pixels being lit with different colors. At a sufficient degree of magnification the letters would disappear and you would perceive only the pixels.
When you watch a movie, you perceive the appearance of objects in motion. No motion is actually occurring, however. You are really observing a succession of still photographs being presented in rapid sequence. Because each image registers slightly longer on your retina than it actually appears on the screen, your brain is able to meld this succession of stationary objects into an illusion of motion.
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