If God Ever Stopped Intervening In Nature....

A: "I am an elephant".
B: "I am a mammal".
Z: "I am an endotherm".

Did you mean to put "objective" in that sentence? It seems to me that it would make more sense if you'd said "subjective" instead.

With logic we construct a long chain of syllogisms, each producing the premises for the next link in that long, long chain. Also with logic, we construct theologies and all kinds of other extremely intricately interwoven webs. Let one single link be wrong and the entire thing can very quickly unravel faster than a knit sweater in a comedy routine.A possible analogy could be navigation by dead reckoning. You know where you are starting from, you know your heading, and you know your speed (together, those last two constitute your velocity vector). After a given period of time, you know where you are. Or do you? What about drift due to wind and currents? What about inherent inaccuracies in your compass and compass reading, et al? When we bought our own 17-foot boat, my father took the seamanship courses from the Coast Guard. You sail out of Newport Harbor and head to Santa Catalina Island ("26 Miles Across the Sea"). As he told me, if your heading is off by even one degree, then you will miss the island altogether. In another example, when he was much younger he spent one summer or longer helping a friend mining. They wanted to extend a mine shaft to join up with another mine shaft. They know exactly where that other mine shaft was and how to dig to connect to it. They never found it, even though all their measurements were dead-on accurate. You need only be off by a very little to miss the mark altogether.In Quartermaster (Navy) training, you use dead reckoning to estimate where you should be, but then you always go out and look at where you actually are (eg, shoot astronomical readings and calculate your position). In USAF tech school, a fellow student was doing flight training and he said that his instructor would have to tell him to pull his head out of the cockpit and look at what was actually out there. Admittedly, a Moody Institute film shown at a private pilots' meeting (my father also had a commercial flight license) gave examples of our senses being fooled when we should instead be trusting our instruments (eg, somehow getting inverted and mistaking the city lights on the ground for the stars). But the main point remains that wherever our logic / dead reckoning leads us, we still need to every once in a while pull our head out of the cockpit and figure out where we really are. There's even a story attributed to Carl Sagan of a toast given about physics and metaphysics, in which the physicist comes up with a promising idea which he then puts to the test in a laboratory and, finding it to be nonsense, drops it, the conclusion of which is that the metaphysicist has no laboratory in which to test his ideas.You speak of a chain from A to Zed (having listened to the original "Hitchhiker's Guide to the Galaxy" and having viewed the original BBC TV production of that work, I know what "zed" means). That is 26 stages. What is the probability that 26 stages of reasoning will produce a true result? That probability should be
P = p ²⁶, where p is the probability of any single step of being true.OK, each stage can be true or false. That would imply a 50/50 chance. So what is 0.50²⁶? 0.000000015, or 1.5 10^-8, or about 15 chances in one billion. In comparison, our chances of willing a state lottery of 5 numbers from 1 to 50 plus one meganumber from 1 to 50 is 7.87 10^-11.Let's make this extremely friendly and let's arbitrarily assign a 90% probability for each and every stage of A to Zed. That would be 0.065 or 6.5 10 ^-2. 6.5 chances in 100. Still not that great. Oh, you can go directly from A to Zed totally regardless of whether A is true or not. We're talking about logic here, not truth nor reality! You can logically construct any number of logically valid constructs of any possible degree of validity, but until you can establish the truth of their premise, they are nothing more than mental masturbation (line from Miami Rhapsody, "My second favorite kind."). Yes, but you must still be extremely rigorous in every step of your logic. And you must be extremely rigorous about the truth of your premises. 26 stages from A to Zed. If you slip up at any one single step, then you have invalidated the entire intricately webbed chain.Or to return to the Navy navigation problem, what happens when you cannot get a fix? I once worked with a WWII Army Air Corps navigator. They called their aviators' wings "silver leg spreaders", since they gave them access to a lot of intimate female contact -- one psychologist shared with us that the free-wheeling sexual activity of the war years is what led to the sexual repression of the 1950's. During one flight where they were transporting nurses, one nurse was telling him that she had always been partial to navigators, but he was too preoccupied with the fact that the weather had not allowed him to get a proper fix for far too long.Early in my college career (far longer than that of most), circa 1970 I had become tired of asking why everybody backed off to learn that my Sun was in Scorpio, so I decided to learn about astrology. Sun signs are extremely easy (they're the same each and every year) and are only one tenth of the more complete picture. Indeed, astrology creates a logical web that is as complete and intricate as any theology's. But if its most basic premises are false, then what good is it? The same with the legion of theologies: if their most basic premises are not true, then what good are they?Logic can still tell us how to test the various theologies. How many are able to withstand the test?

Say we assume that the first premise has a 50/50 chance of being true. Every subsequent verified observation or deduction increases the chance of A being true or false as the case may be. As the chain increases every preceding step is verified anew and has an increasing probability of being correct. So by the time you get to Zed your chances of being correct have increased by (insert math here) a bunch. ringo is saying that you can not actually stick your head out and see where you are and I disagree. There is a reality that we can use to verify our perceptions of it.

The first predicate is the result of the seventeenth, which is the result of the eleventh. They are all inter-related but none of them is directly connected to what "is" (if inded there is anything that "is"). It's all constructed on constructs. "Likely", yes. Absolutely certain, no.

Not quite. There are perceptions of reality that we can use to verify other perceptions. If we arrive at our destination, our perceptions were internally consistent. You might think you've arrived in India when you've really arrived in the West indies.

This particular proposition is not correct. Not even close. Let me provide a few concrete counter examples examples.1. How many observations of the stars and the sun rising or setting would it take to settle the question of whether a geocentric or heliocentric model of the solar system is correct? It turns out that simply making assuming a heliocentric model of Copernicus rather than a heliocentric model, even after applying those goofy epi-cycles in both models produces comparable accuracy in predicting positions of planets within the solar system.2. How many years worth of precision observations of the orbits of say the earth and mars would it take to resolve the question of whether Newton or Einstein's formulation of gravity is correct? Even determining the difference between the Newtonian or Einstein predictions for the orbit of Mercury would not be easily apparent with even a decade or so of observation. Each observation would confirm both formulations equally well.In fact, both observation, and a correct chain of logic are required. It is not enough to simply use a match with an observation to confirm that a particular chain of logic is correct. Only particular observations properly designed to distinguish between competing premises can do that. One observation of stellar positions during a solar eclipse does something that a thousand observations of Mars or Mercury using the best available equipment cannot accomplish.3. How many observations of would be required to confirm the difference between Galilean transforms and Lorenz's transformation. Well it turns out that as long as we observe objects at 'ordinary speeds' we'll never be able to tell the difference.Of course a single, properly placed observation can rule out a theory, hypothesis or model, but unless you are sure that you've made such an operation, the fact that an observation is consistent with a particular hypothesis is woefully insufficient.

When you say 'perceptions of reality' what exactly are you referring to? Something is causing your brain to have perceptions.

Certainly this is true. When I speak about using logic I assumed that it was understood that I meant that you have to use all of it. Obviously, I am not saying that it is impossible to be wrong but rather that it is possible to be right. As the web of logic expands and the points of corroboration increase so do the odds that our perception of reality is approaching reality. If we can be closer to it or farther from it then it must exist.

How do you know it's impossible? How can you know with absolute certainty that it is impossible that this is all in your imagination? Maybe this is all inside your own head and you are arguing with yourself here?There may well be excellent grounds for thinking this is not the case. We might even say we (tentatively) know this is not the case. But absolute certainty? No.How have you established it's "impossible"? In which case the "absolute truth" in question once again becomes the tautological (AKA trivial) "reality is real".So back where we started......

What does "all of it" mean? How do you know that you are not following only the lines of inquiry that produce corroboration?Yes it is possible to be right, but increasing points of corroboration do not necessarily increase the odds that we are right. It may well be that only a few lines of inquiry can produce a lack of corroboration and that we have no clue how to find them. The history of science is full of examples of exactly that.

Your brain gets its input from your senses. It can also replay its own memories in sometimes bizarre ways - e.g. dreams. Drugs can alter the brain's operations. The body's own chemistry can cause the brain to scramble perceptions - e.g. mental illness.Why would you assume that some perceptions must come from something "real"?

Yes, I was responding to ringo's use of the word objective:

But you doubt the laws of physics, so how can you make any predictions, if you doubt the science your predictions are based on? Absolute chaos is hard to imagine, but I suppose it would be a universe devoid of any logic at all. Nothing could be relied upon. No uniformity of any kind. Either that, or an afternoon at the DMV. We can know that A is A absolutely. Or that True cannot also be False at the same time.

We can have a high degree of confidence in something without having absolute certainty in it's absolute truthfulness. Consider the following - "This sentence is false".Is this sentence true or false? This is an example of a definitional truth of the sort Ringo has been calling trivial. But let's have some fun....A = 1/3 + 1/3 + 1/3 =1A = 0.333R + 0.333R + 0.333R = 0.999RA =1 and A= 0.999 RecurringCertainly A = A. I'm not denying that at all. Mathematics is as about as absolute as we are ever going to get.I just wondered if you still think it's as obvious that A is A absolutely as you perhaps first thought?Edited by Straggler, : No reason given.