After I thought more about this, I came up with a good analogy to reveal the faulty assumption that, because primordial life started shortly after the Earth cooled down, then the probability of primordial life must be high.
Consider this: you walk into a saloon and sit down at your very first game of poker. On your very first hand, (or 2nd hand, doesn't matter) you are dealt a Royal Flush. From this you conclude that Royal Flushes are pretty common in poker, right?
That is a good point about the sample size being larger than 1 for complex life. But I believe that it highlights the real sticking point, namely the origin of the primitive, bacterial form of life. For that, we have only a single data point.
And the assumption of the Rare Earthers, that origin of bacterial life is common because it occurred shortly after conditions permitted, that assumption is FAULTY!
The reason is that you can't infer a causal relationship between 2 events, even if they are temporally close, when you have just a single occurrence.
It's hard to understand this, because there are few singular events in our experience for which we cannot intuitively estimate a compound probability. The origin of life is one of them. The origin of the universe is another.
I am always amazed at the inability of people to admit simple lack of knowledge about certain questions. The probability of life ocurring can either be determined through measurement of actual events (in this case, we have only a single data point) OR, the alternative is to calculate it in terms of combinations of other events whose probability we can measure.
Now, the combination of molecular events leading to the first replicating cells on Earth is COMPLETELY UNKNOWN!!!! Let me repeat that: There is absolutely no specific model for the origin of the first replicating cells on this planet which is detailed enough to allow for computation of a probability from a combination of molecular events.
Therefore, until this probability is determined, it is completely pointless to talk about the number of galaxies, stars, planets, etc, because as long as the 'fi' term in the Drake equation is utterly UNKNOWN, the final product is UTTERLY unknown as well.
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I run gvim on Win98 and Windows Me on a regular basis and it runs perfectly on both.
Consider this: you walk into a saloon and sit down at your very first game of poker. On your very first hand, (or 2nd hand, doesn't matter) you are dealt a Royal Flush. From this you conclude that Royal Flushes are pretty common in poker, right?
Wrong!
mhack
And the assumption of the Rare Earthers, that origin of bacterial life is common because it occurred shortly after conditions permitted, that assumption is FAULTY!
The reason is that you can't infer a causal relationship between 2 events, even if they are temporally close, when you have just a single occurrence.
It's hard to understand this, because there are few singular events in our experience for which we cannot intuitively estimate a compound probability. The origin of life is one of them. The origin of the universe is another.
mhack
Now, the combination of molecular events leading to the first replicating cells on Earth is COMPLETELY UNKNOWN!!!! Let me repeat that: There is absolutely no specific model for the origin of the first replicating cells on this planet which is detailed enough to allow for computation of a probability from a combination of molecular events.
Therefore, until this probability is determined, it is completely pointless to talk about the number of galaxies, stars, planets, etc, because as long as the 'fi' term in the Drake equation is utterly UNKNOWN, the final product is UTTERLY unknown as well.
mhack