@TurboLung,
TurboLung;71245 wrote:oh dr. contradiction, don't we remember this?
or perhaps, this;
:Not-Impressed:
OK we seem to be stuck over some childish mudslinging. Let's try and move on - for my part I apologise if my words caused offence. There's no need to apologise for your own insults, as I'm not offended by them and they haven't prevented me from answering your questions. I didn't mean for the injection of a little cut and thrust into the debate to get in the way of providing answers.
I'll anticipate what you might of meant by (I paraphrase) "when did the molecules decide to live".
When did self-replicating molecules reach such a degree of complexity that they began to display the qualities of life shared by all organisms which display such qualities?
The evidence points to a common ancestor of all multicellular and single-celled life. The form is likely to have been prokaryotic rather than eukaryotic as eukaryotes are more complex, carrying a nucleus and other cell furniture not found in prokaryotes.
As you can see from the diagram the first branch is - based on the best evidence and arguments - thought to be Firmicutes. These gram-positive bacteria are simpler than gram-negative ones, lacking an additional layer of outer cell wall.
Modern Firmicutes looke like this:
So this is the best example of what the very first forms of life might have been like.
That's my hypothesis, anyway. I can think of objections - it's always risky to assume ancestral forms share characteristics with modern ones. However, these are the simplest lifeforms (quibbles over what makes a lifeform aside) that are known to science today and the fossil record records a gradual lack of complexity the further back we go and logically this ties in with natural selection.
So the basal form of all life was probably a lot like this. They obviously didn't live inside human guts - probably in snottites.
Fossils of such organisms exist in the Paleoarchean rocks - which range in age from 3,200,000,000 to 3,600,000,000 years old.
There are contested claims about fossil bacteria from even older rocks, though the only clear fossils of recognisably fully-formed prokaryotes date from the Paleoarchean.
So, circa 3,400,000,000 BCE as an estimate.
Quote:i am glad you have finally made it clear that you throw your faith into possible answers the float about theroies in their infancy that have more holes than swiss cheese..
You're conflating two different issues. Scientific consensus is pretty much reached over the criteria for life. There is a bit of controversy over the exact place where the line is drawn, as there is on many issues, but the quibbles are pretty trifling and irrelevent really. I'd ignore them for all practical purposes - but it seemed dishonest not to note that there is some minor quibbling.
That aside... I don't see any answers other than "possible" answers - by all means elucidate a counter structure that has better arguments to support it. So where it comes to me "throwing my faith" - at the risk of seeming martyrly I feel like I've had to state my position on this a dozen times already - I trust the best made arguments for which there is the most evidence.
This is a leap of faith to a degree - but it strikes me as the shortest jump of all the alternatives, and the one which actually takes me to a place I find a lot more interesting to be than either the paralysis of abiding by Cartesian doubt or the myths of religion.
What alternative do you suggest?
1) Doubt everything - go nowhere.
2) Trust the scientific method - go places I find interesting, that tell lots of fascinating stories backed up by interlocking theory and evidence that has practical application to where, how and why I live. Increase my practical understanding of things.
3) Trust in myth - a lot of confusing and contradictory ideas backed up by nothing but anecdotal evidence that seems to offer a satisfying metaphysical meal until you try and query it when you are invariably told that you are making wrong interpretations, have to exercise poetic license, or that you are seeking answers to questions that should be left unspoken.
4) Or what?
I like option 2. Sometimes I indulge in option 1 because I like a bit of sessile indulgence from time to time - though it's tedious to overapply it. Option 3 is merely of use for fiction and imagination as far as I see it - useful for exercising certain human faculties, but far inferior to option 2 for actually learning about life the universe and everything. Others seem to like it, but it just doesn't do anything for me. It's too easy and boring.
Quote:so, the theory in its infancy you so whole-heartedly embrace holds little validity, but to question the theory in its infancy is unacceptable in your eyes?
This is just the same objection as the one that inspired my response but reworded, as far as I can tell. If I think the critique is valid then I'll not dismiss it. If it's a pat observation made and debunked over and over again I will.
Saying "it's just a theory" is pat - because scientific theory is a poweful tool.
Saying "it's not complete" is pat - because no theory is (the theory of special relativity accounts for some oddities in the theory of gravity, and the links you posted point out some holes in the theory of special relativity) and you have yet to point me to a more likely alternative.
I'm not "whole-heartedly" embracing anything - but I'll throw my lot in with the infant. Why? An infant is weak and small, but also holds potential. What else is there? If the baby's all there is - I'm with the baby.
He seems to be growing fast.
Quote:exactly, but the links show that other scientists can easily find replacement theories, even when it comes to einstein.
The links shows that other scientists can hypothesise about apparent problems with the theory - it does not show that they can junk it or replace it. No one in the links seems to propose a new framework, they highlight a few issues that need further examination.
As I already admitted, it may need tweaking, rebuilding or junking as a result of these issues, but it has not been "disproven" - it just doesn't seem to account for certain things and there is currently no better alternative.
So if you want to try and understand and predict the things Special Relativity seeks to predict there is still nothing better to do it with than SR - despite a few areas of objection.
Quote: theories can easily be muddied by other scientists and eventually you start to wonder if you can take on board any theories without a grain of salt.
True, but what's the alternative?
Quote: so, what i am pointing at is, yes, your theory in its infancy may be hold some truth, however, it is not something we can accept as fact (as you so readily do). especially when it is not widely accepted by scientists and especially when it is full of holes.
Colloquially, I accept as fact that which is the best argument, and I don't see any better arguments than abiogenesis. By all means fight a negative campaign - but what have got to propose that's any better?
Scientifically, I accept as fact what can be observed as true - because science takes that conceptual leap which philosophy distrusts - I don't accept abiogenesis as fact - I accept it as theory, which is an organising structure of facts.
Quote:i would say that it could be considered dangerous. it might be dangerous to believe a story based on a few facts, while filling in the gaps. do you think a court of law would base their decision on someone's testimony based on a few facts and the rest assumptions?
It happens regularly. Witness testimony is assumed on it's merits - not hard facts - and cases are often built on little else. Judges and juries are assumed impartial.
As an example - pretty much all rape convictions. There's no real physical evidence to seperate consensual sex from many cases of rape - so the testimony of those involved, character witnesses, and so on, are required to make or break a case.
Quote:my theory is that stars run on double-a batteries. well, it must be true because stars glow and need some type of power... there is my theory and it frames a fact. do you believe it?
Your
hypothesis is that stars run on AA batteries.
Your next step is to imagine some ways that you could test this hypothesis through calculation, experimentation and coordination with currently accepted theory. An easy test might be to figure out the amount of energy taken to power the reactions that take place within a star and see if an AA battery could supply such energy for the lifespan of various stars. A problem to overcome would be to explain how all the current theories about solar fusion are wrong. You would have to show how they are better explained by the insertion of a power source heretofore thought to be produced by human manufacture alone.
If your research shows that the hypothesis was wrong then you should review your hypothesis. If you are a 'bad' scientist you might refuse to admit to the shortcomings and move on anyway.
Once you run your experiments and make your calculations you can then submit your research to peer review by writing a paper about your hypothesis and the method by which you proved it works.
Peer review is the first process which weeds out bad science - your papers will be circulated about a number of experts in your field who will double check your calculations, review your experiments and raise objections or point out things you might have missed.
If your paper passes peer review, or is rewritten to account for peer review and subsequently passes it again, you can use it as an article for a scientific journal, letting the world know about your hypothesis. The journal will be read by huge numbers of people interested in the field.
If no one finds the hypothesis presented in the journal to be problematic, and if they find it a useful tool to explain the power of suns, then it is said to have passed into "scientific consensus", and can be tentatively termed a theory. However, during this period if scientists point out issues with it it will probably need reworking in order to qualify. If it gets a thorough junking at this stage it still can't be claimed as a scientific theory. However, if your working convinces the scientific community in general that previous theories or hypotheses about the sun were wrong and the "battery theory" is a better explanation then it's obviously got some merit.
Perhaps the "battery theory" is so good that it helps generate a new level of understanding - perhaps the qualities of AA batteries help explain why suns go nova. Perhaps based on the qualities of AA batteries scientist can better predict the lifespan of the stars.
If such a hypothesis passed peer review would I believe it? It would be hard to, I admit - I'd want to see the reasoning behind it before I did so. But the journey it takes from a hypothesis to a theory will have had to demonstrate it's plausability in order to be undertaken at all.
The problem here is that the colloquial use of the word "theory" is actually incorrect and pervasive to the point where almost everyone outside of the scientific community uses the term when they mean "hypothesis".
Such misuse is even found in a lot of popular science books, and pervades the media. So it's easy to see how confusion arises.
Quote:how do you know your theory in its infancy hasn't been partially worked on by "bad scientists"?
It probably has been, but the aspects of the theory that have passed through the process outlined above are those that carry weight and will be pretty robust. The bad science will have been exposed and those scientists who provided it called into question.
Quote:you know, and i know, that everyone would be interested in the beginning of life. now you are being silly.
No I'm not - some people are just blase about the issue. A few are highly religious, for example, and don't want to know anything that might contradict their religious beliefs.
Quote:but a net has more holes than framwork. :rolleyes:
And is used to catch fish - the analogy wasn't meant to demonstrate a comprehensive set of simularities.
Quote:if there was evidence, then it wouldn't be an assumption. you assume when you don't have evidence.
Science is born partly out of the philosophical observation that you can't be certain about anything. However, science makes the conceptual leap away from this in that it takes as read that facts based on observables lead you closer to the truth. Philosophy distrusts this jump because of philosophy's reluctance to seperate the nomenal and phenomenal. In philosophy there are no facts because ideas such as "am I the sage who dreampt he was a butterfly or the butterfly who dreampt he was the sage" are regarded as wise (and why not?).
Philosophy looks at that problem and says "interesting point" and subjects the question to various lines of enquiry depending on the school.
Science looks at that problem and says "you seem to be the sage, people encountering you who show no signs of delusion corroborate that you are the sage, butterflies have never been known to utter philosophical axioms, biologists say you display all the characteristics of a human and hardly any of a butterfly, so we think it's a pretty safe bet that you are the sage."
So science does deal in evidence and makes certain assumptions in order to link the pieces of evidence together, the process of reseach, testing, peer review, scientific consensus reinforces or junks those assumptions depending on how solid they turn out to be. Facts, laws and theories are still types of assumption, it just seems that no one can offer a better assumption.
To judge science by philosophy's standards, as richf seems to do, strikes me as fair enough on a philosophy forum. However, as Aedes points out, the end resort of this might be some sort of paralysis where the assumption that an observable is unreal is just as valid as the assumption that it is not, regardless of criteria - which is pretty impractical (as far as I can tell). I can respect the intellectual rigour, but I think it would be boring and impractical to answer "you can't really tell" to each and every question - even if it's true because the nature of reality is ulitmately unknowable as far as I know.
The view you seem to advocate above - that there must be a more concrete way to discover things - well, what is it? I'd love to know, but I think it's quite pie in the sky to claim we can reach statements of fact without making any assumptions. Even "I think therefore I am" is a subject of debate on this very forum.
Quote:
i have put you in your place with the quantum mechanics argument. do you agree?
If you want to call me on this I concede - though I will raise the objection that you seem in this case to be standing solidly by a hypothesis which is actually a whole lot less scientifically sound than may of the others that you have raised loud criticisms against.
So I'll stand down on quantum by all means as it appears I have a lot to learn.
I'd still like to know where Hawking talks about men walking through walls though, I have a copy of his book and don't know where the story is told.
