The thing is, we don't stop at logic. We test our logical conclusions against reality. If they match, we can be confident that our logic is good. If not, then there is a flaw in our logic or our premises (or possibly in our observation of reality).
Contradictions prove that the world is not logical.
- Thread starter Ted Grant II
- Start date
I do not assume humanity will last that long. I strongly suspect our resources will not last much longer. We are probably overdue for a big asteroid. If natural disasters don't do it, humanity will probably destroy itself. We do not even know yet that it will be possible to go to other systems. At this time, it seems impossible. Mars is probably no good for long term but will be necessary as a stepping stone.
Humanity's long them survival probably depends on colonizing other systems yet I suspect we have a short window of opportunity.
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Humanity's long them survival probably depends on colonizing other systems yet I suspect we have a short window of opportunity.
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DaveC426913
Valued Senior Member
OK, so you were originally suggesting humanity was doomed in 5 billion years when engulfed by the expanding sun. I take it you're no longer suggesting that is our ultimate fate. Our fate will be determined much sooner, by some other disaster.
No it doesn't. It depends on staying on Earth.
DaveC426913
Valued Senior Member
Earth has limited resources; we will eventually run out.
Earth also has limited room; we will eventually outgrow it.
It is also vulnerable to disaster. We need to have offsite backup.
Ted Grant II
Registered Senior Member
I have no defense, because you are not attacking me.
I agree that there is no "must" involved.
It still means we can't be absolutely sure that our reasoning is sound.
Our so-called proofs can never be more than probably true.
If we wish to be rigorous, our "proofs" are not proofs.
If we don't mind being sloppy, then they'll do nicely.
Ted Grant II
Registered Senior Member
You make a good point, which I neglected to address.
Perhaps I should have noted the ultimate doom that lies ahead, in the far distant future, when all the stars have died out and space is a uniform 4 degrees above absolute zero.
The second law of thermodynamics is inescapable, allegedly.
Ted Grant II
Registered Senior Member
Endless reproduction, reading the Bible until we understand it and playing all of Beethoven's sonatas in less than 40 hours.
DaveC426913
Valued Senior Member
This is why we create axioms.
"If we can believe our eyes, then we can observe the world and make statements about it." (This does not declare that we can believe our eyes).
"If addition is commutative, then 1+2 = 2+1."(This does not declare that addition is commutative*).
*actually, this isn't an axiom - addition is commutative by definition. But you get the point.
DaveC426913
Valued Senior Member
The is a deepity.
What difference does it make?
We shouldn't live our lives now, because it will be undone a quadrillion years in the future?
Ted Grant II
Registered Senior Member
Actually, as I understand it, LOGIC itself is fundamentally self contradictory, not just examples.
The very foundation of logic has easily been shown to be flawed.
In order to fix it, you have to add arbitrary rules.
Then when the arbitrary rules are employed, further contradictions are found.
In order to fix that, you have to invent even more arbitrary rules.
And so it goes on.
For more about this, I recommend reading Kurt Godel's famous paper on the subject.
or better still, Principia Mathematica.
It makes excellent bedtime reading.
Ted Grant II
Registered Senior Member
The trouble is two-fold.
We cannot prove the axioms. They just have to be accepted as self-evident.
The logical steps in a proof, using the axioms, require explanations, as we may be making unjustified big steps, unwittingly.
The missing explanations, when provided, may require further axioms and further steps.
As my mathematics teacher told me, when criticizing my proof of Pythagoras's famous theorem,
"You must show all of the workings".
The problem, simply put, is it depends on the meaning of that little word "all".
Ted Grant II
Registered Senior Member
Agreed.
I was merely answering the question, "What is our ultimate purpose in the long run".
There is no long run.
Ted Grant II
Registered Senior Member
By the way, at the centre of our galaxy, the so-called Milky Way, there is an enormous black hole.
Every second or so, a star plunges into the black hole, along with any planets, moons, books etc.
Imagine the screams of the poor aliens, just after their television announcer says "Goodbye" (with no "Good Luck" attached).
All their Alien Religious Holy Books, completely unknown in any other star system, stretched and crushed, then vaporized.
Well at least you had the decency to keep your Cowpat answer short
Who is Beethoven?
Another shining example of a loving caring god
While the alien scriptures (along with the aliens) are now lost to us can you speculate their god was the same as ours?
With a similar narrative?
DaveC426913
Valued Senior Member
You riffed on an assertion that Ted made in post 5.
I conflated the two in my mind.
Mia culpa.