I was having a discussion the other day about how you know when you know something? According to Webster’s New World Dictionary, the word “know” is a verb tense that means one of four things. The first is “to be well informed about.” The second is “to be aware of.” The third is “to be acquainted with.” And the final is “to recognize or distinguish.” I have came to believe that our question should have been, “How do we know when we understand something.”
We cannot understand anything that we cannot explain in words, for understanding requires reasoning and reasoning requires words. If you think that you know something try explaining it to someone who does not. You may find that you cannot find the words to describe your understanding of what it is that you think you know, which is a sure sign that you do not know it, but just ‘think’ that you know it. We all some assumptions about what words and ideas mean, and what it means to understand or “know about” something. Now what would you have to do in order to make an inference that another person actually understands what they said they understood?
You would listen to or read their words, evaluate what they said and the authority with which they spoke. Now a bum on the street is as capable of understanding and explaining that understand as well as any man, but if he was explaining how Nuclear Magnetic Resonance Imaging was able to draw a picture of the inside of your brain you would not give him the same credence as you would Radiologists who read the pictures. As well, you would discount his explanation even without ever talking to a radiologist or a physicist just because he was a bum on the street. In most cases, your dismissal would be justified, but what about the bum who had made his living for 20 years working on NMRIs? His explanation would be as sound as any radiologists or physicist, but his status as a bum would close your ears to his understanding.
“The acid test for understanding is rather simple; if a person says he or she understands something, then the person should be able to explain to others what it is that is understood. It come down to the premise that if you can’t explain what you know, then chances are you don’t know it. But there are functions of knowledge that go beyond explanation. In addition, as has been stated many times on the ADPRIMA site, “anything not understood in more than one way is not understood at all.” WHAT IT MEANS TO UNDERSTAND SOMETHING
There is a further complication, just because you, or another, knows a subject well enough to explain it well does not assure that which being explained is a true depiction of what is being explained. How do you know how the universe was created? There are numinous explanations, all explained well and well understood by those doing the explaining. To touch on just two:
The Materialist holds that matter is the fundamental substance in nature, and that all phenomena, including mental phenomena and consciousness, are the result of material interactions. They believe in a cause and effect universe with each and every effect caused by a previous cause, with the first affect being the Big Bang which set everything into motion and is still setting down. They believe that even the motion of the neurons and the firing of the synapses in our brains are just a continuation of the event set into being by the Big Bang, the Big Bang is their god creator. However, what caused the Big Bang is not considered. They deny the present of a soul or any god other than the ones created by man. This is indeed a religion! Its name is Scientism, which is the belief that only science can deliver the answers as to what the universe is, how it came about, and how it works. They do not concern themselves with such question as to why there is anything instead of nothing.
On the other end of the spectrum are people like me who hold that God said, “Let there be light” and there was light.
The Cosmological Argument
This is the first empirical proof of God’s “existence.” The argument can be found in Aristotle’s Physics Book VIII.4-6,
5 “From what has been said, then, it is evident that that which primarily imparts motion is unmoved: for, whether the series is closed at once by that which is in motion but moved by something else deriving its motion directly from the first unmoved, or whether the motion is derived from what is in motion but moves itself and stops its own motion, on both suppositions we have the result that in all cases of things being in motion that which primarily imparts motion is unmoved.”
6 “The eternity and continuity of the process cannot be caused either by any one of them singly or by the sum of them, because this causal relation must be eternal and necessary, whereas the sum of these movents is infinite and they do not all exist together.” 
Here then is Aristotle’s argument: 1. A mover is needed to explain motion; 2. This mover is eternal and one; 3. This mover is the first mover; 4. The mover has no finite size and is therefore infinite; 5. The mover is in the center or on the circumference of the universe.
This argument was used by Aquinas in his Cosmological argument:
“It is certain and evident to our senses, that in the world some things are in motion. Now whatever is moved is moved by another…But this cannot go on to infinity, because then there would be no first mover…Therefore it is necessary to arrive at a first mover, moved by no other, and this everyone understands to be God.”
First, the reader will see clearly that he bases his argument on sensation and motion. I suggest the reader refer to my theses against empiricism. Certainly, when Aquinas says that “Now whatever is moved is moved by another” this cannot go on infinitely because then there would be no first mover”: he asserts that there must be a first mover. The problem is, this assertion functions as the reason to reject the infinite regress and the conclusion. This is a fallacy. I have also been struck by Hume’s rejection of the cosmological argument. He saw that observations of the effect would be the only basis for understanding the cause. Hume gave an example, that if we heard the symphonies of Beethoven, we would understand his logical, structured and mathematical genius as well as his artistry and creativity, but this would tell us nothing of the fact that he loved sports and was the quarterback of Bonn University. Therefore, our knowledge of the symphony would leave us with spurious conclusions about Beethoven.
Now, is the motion of the Prime Mover accidental or essential? If accidental, there is no necessity for it to always move and could, in theory, stop moving. Yet Aristotle proved that the motion was eternal. If the motion is essential, a question must be answered: is the motion of the mover of the same species as that which it causes to move? An eye on a stovetop heats a pan and at the same time is getting hot. In this case the essence of motion is the same in both. Yet this is the problem with empiricism. One particular does not prove a law or a universal truth. Does the Geometry teacher who teaches a Geometry lesson learn the Geometry lesson? No, the teacher already knows the lesson. Therefore, the motion of the Prime Mover can neither be proven accidental or essential. Therefore, a self moving mover does not explain motion.