26 Mar 14
2 edits
Originally posted by wittywonkaI can guarantee you will get infinitely more sense from these infinitely more intelligent guys then from him:
Let me go about this a different way.
Physicists assume that tomorrow, the laws of gravity will behave the same way that they do today and that they did yesterday. It's true, they can't know for sure, but given that physicists have repeatedly, repeatedly measured the acceleration of gravity on Earth to be 9.8 m/s^2, it's a relatively safe assumption, u ...[text shortened]... ientific induction, that tomorrow, the half-life won't somehow change to half of what it is now.
http://phys.org/news/2014-03-crows-basic-aesop-fable-task.html
http://phys.org/news/2014-03-goats-clever-previously-thought.html
27 Mar 14
2 edits
Originally posted by RJHindsOkay, let's say that over the course of millions and billions of years,
Scientists even speculate that conditions in the beginning had to be different than they are today...We can not test it.
1. the composition of the gases in Earth's atmosphere changed dramatically;
2. the force of contact between tectonic plates on Earth's surface crushed rocks into one another and changed the pressure exerted on those rocks;
3. the Sun's magnetic field interfered unpredictably with the Earth's magnetic field;
4. the temperature on Earth's surface fluctuated wildly.
These are all actually reasonable assumptions, as you suggest. However, I refer you back to my first post addressing your concern with geologists' assumptions, where I mention that:
"For most radioactive nuclides, the half-life...is not affected by external factors such as temperature, pressure, chemical environment, or presence of a magnetic or electric field."
http://en.wikipedia.org/wiki/Radiometric_dating#Radioactive_decay
In other words, scientists have empirically measured the half lives of various elements under a wide range of conditions, including those like I list in #1-4, and they have found that the half lives of those elements are not affected by such changes.
So unless you can propose another possible way in which the Earth could have changed over time that scientists haven't tested for, then I think your criticism again does not hold water.
And again, if you want to reject the assumptions that these geologists are making, that's fine. But the only way to do so and still live a rational existence is to reject the same methodologies and assumptions that scientists in other fields use, too--like rejecting the methodology behind the inference that testing cars under a wide variety of conditions is still scientifically sufficient evidence for assuming that those cars are both safe and representative of all cars on the road.
EDIT: I do find it ironic that you believe your argument that "scientists speculate that conditions in the beginning had to be different"--i.e., that scientists make assumptions about how the Earth developed--constitutes a valid argument against the use of assumptions to draw conclusions in other disciplines of science.
27 Mar 14
4 edits
Originally posted by wittywonkaAutomobile manufacturing and testing have been going on for a hundred years with the resulting improvement in the design an functioning of new models. Any assumptions in the functioning of those automobles have been tested over and over and when failures occur adjustments have been made. Those types of assumptions that can be tested is not what I object too.
Okay, let's say that over the course of millions and billions of years,
1. the composition of the gases in Earth's atmosphere changed dramatically;
2. the force of contact between tectonic plates on Earth's surface crushed rocks into one another and changed the pressure exerted on those rocks;
3. the Sun's magnetic field interfered unpredictably with ...[text shortened]... lid argument against the use of assumptions to draw conclusions in other disciplines of science.
Radiometric dating is more like using an hourglass to measure time. The hourglass only works for a short time under controlled conditions. You know that the sand will take an hour to fall to the bottom. That is the only real science about it.
An hourglass is only useful if we saw it turned over and observed that the bottom glass was empty. Unlike the hourglass, we do not know how much of each isotope was in the rock in the beginning. That’s because we did not observe what happened in the past when the rock formed. Neither can we travel into the past to make the necessary measurements. All we can do is guess. This is the fatal problem that essentially makes radioactive dating useless as a primary method for determining age.
27 Mar 14
2 edits
Originally posted by RJHindsLet's address the concerns you raise in your hourglass analogy one at a time.
Automobile manufacturing and testing have been going on for a hundred years with the resulting improvement in the design an functioning of new models. Any assumptions in the functioning of those automobles have been tested over and over and when failures occur adjustments have been made. Those types of assumptions that can be tested is not what I object to ...[text shortened]... oblem that essentially makes radioactive dating useless as a primary method for determining age.
To me, the most weakest concern you (and the video you shared) raise is the notion that we can't be sure that the rate at which the sand flows to the bottom hasn't changed over time.
Yes, fundamentally, you are right. I concede that we cannot know with certainty that the rate of flow of the sand is constant over time without having seen every grain of sand flow to the bottom in the first place.
But, again, as I keep saying, where you lose me is your insistence that the uncertainty in this scientific observation is somehow different than the uncertainty inherent in the application of the scientific method in virtually every other field. Because if you can't demonstrate that there is some fundamental difference in the uncertainty of geological science and that of other sciences, then you are almost certainly living out a life of rational contradiction.
How is it that you presumably accept that fundamental laws of gravity will work the same tomorrow as they do today, whereas you want to say that the fundamental properties of radioactive decay will not, because the science that determines them is based on "unproven assumptions"?
27 Mar 14
Originally posted by wittywonkaBecause I live today, not in the distanct past and I know of nobody that lived a million years ago to tell me about it. We have no written history that goes back more than a few thousand years.
Let's address the concerns you raise in your hourglass analogy one at a time.
To me, the most weakest concern you (and the video you shared) raise is the notion that we can't be sure that the rate at which the sand flows to the bottom hasn't changed over time.
Yes, fundamentally, you are right. I concede that we cannot know with certainty that the r ...[text shortened]... ive decay will not, because the science that determines them is based on "unproven assumptions"?
27 Mar 14
3 edits
Originally posted by wittywonkaThe assumption that the half life of each radioactive element stays constant with time is, I suspect, probably much less of an assumption than your realize. I note you from your previous posts that you probably think that assumption was just based directly inductively i.e. on the fact that the half-life has never been observed to alter in the past. But, actually, it is based on something much more than that because the half life of each radioactive element is actually determined by the laws of physics and, to be more specific, the laws of physics concerning the forces between nucleons (neutrons and/or protons ) . Thus, for the assumption of constant half life to be wrong, those laws of physics would also have to be not constant! This would inevitably makes the rationally determined probability of this assumption being wrong to be vanishingly small -without being pandemic and for all practical purposes, you can call it a "fact", and not an "assumption" that the half-life stays constant with time and must have stayed constant in the past or at least couldn't have possibly changed by more than a miniscule amount at most.
Let's address the concerns you raise in your hourglass analogy one at a time.
To me, the most weakest concern you (and the video you shared) raise is the notion that we can't be sure that the rate at which the sand flows to the bottom hasn't changed over time.
Yes, fundamentally, you are right. I concede that we cannot know with certainty that the ...[text shortened]... ive decay will not, because the science that determines them is based on "unproven assumptions"?
27 Mar 14
Originally posted by RJHindsSo once again, simply ignoring what he just said, hands over ears going 'I can't hear you, I can't hear you', like a 5 year old.
Because I live today, not in the distanct past and I know of nobody that lived a million years ago to tell me about it. We have no written history that goes back more than a few thousand years.
27 Mar 14
Originally posted by RJHindsYou also don't know anyone living in the future who can confirm that the laws of physics will work tomorrow in the same way that they do today.
Because I live today, not in the distanct past and I know of nobody that lived a million years ago to tell me about it. We have no written history that goes back more than a few thousand years.
27 Mar 14
Originally posted by humySure, you're right.
The assumption that the half life of each radioactive element stays constant with time is, I suspect, probably much less of an assumption than your realize. I note you from your previous posts that you probably think that assumption was just based directly inductively i.e. on the fact that the half-life has never been observed to alter in the past. But, actuall ...[text shortened]... in the past or at least couldn't have possibly changed by more than a miniscule amount at most.
I'm just using the idea of inductive inference because it seems more relevant to demonstrating RJH's inconsistency in accepting some inferences and rejecting others, even when they're grounded in the same scientific methodologies.
27 Mar 14
Originally posted by wittywonkayes, I gathered that 🙂
Sure, you're right.
I'm just using the idea of inductive inference because it seems more relevant to demonstrating RJH's inconsistency in accepting some inferences and rejecting others, even when they're grounded in the same scientific methodologies.
27 Mar 14
Originally posted by sonhouseI have already said that we know something about the recent past and we can make reasonable predictions about the near future. However, millions of years in the past or future can not be known by scientists.
So all you can do in your world is to comment on things happening right now, not 10 minutes in the past or 10 minutes in the future. So you live kind of the life of a squirrel.