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Comment by robmcm | Hacker News Reader

They claimed there was no evolutionary differences, so either it started it's space journey at the same time our ancestor did, or it evolved in the exact same way...

However the stating of, "zero chance" is rather un scientific.

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>However the stating of, "zero chance" is rather un scientific.

Not really. It's just rounding. Of course nothing has literally zero chance, but sometimes the chances are so low that the epsilon isn't worth mentioning.

He should have said "probability 0", which translates as "almost impossible". The word chance is the tricky one, here.

Well no, "probability 0" means "impossible". I'm not sure what difference you're seeing between "zero probability" and "zero chance", but they mean the same thing.

It's rather pedantic in this context, but "probability 0" and "impossible" actually aren't the same thing:

http://nolaymanleftbehind.wordpress.com/2011/07/13/the-diffe...

In mathematics, probability 0 means "almost impossible". Think about randomly choosing a number between [0,1]. Uh-oh, that set is actually infinite (cardinality aleph 1, technically). Suppose we consider only the numbers in it with 1 decimal digit, i.e. {0, 0.1, ... ,0.9,1}. Every one of them has 1/10 of probability of being chosen. Now, suppose we consider two decimal digits: 1/100 probability of being chosen. Repeat this process and consider no discretization (i.e. there exists arbitrarily small epsilon>0 such that the difference between two numbers in the set is < epsilon).

Then the probability is.. 0! (you see how we divide 1 by the number of elements which are in the set)

But in the end you are going to pick one number or another in that set, so it is not "impossible". Surprise surprise.

Yes, perhaps a just a poor choice of words.

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