Seems to me the diminutive, yet perfectly-formed, Tom Cruise is getting something of a bum rap in these post-Oprah days.

In an interview, Wednesday, with the German tabloid Bild, the world's most `out' Scientologist was reported to have confirmed his belief in the existence of aliens.
We are all, armed with this `earth-shattering' news, implicitly invited to mock the vertically-challenged-one and to speculate as to at which precise time-space location ("Get a life, Heisenberg!")Tom first discovered he couldn't get all the marbles back in the bag.
More than a smidgin unfair I feel, since, if you are amongst those who do not believe in the existence of aliens I've got good and bad news for you.
Good news first, O.K.?
You are not alone.
Bad news?
You just got an F in math.
Here's a true story.
Back in January, 2000, I had the - to me - extraordinary privilege of spending three days with Neil Armstrong.

Neil was the keynote speaker at a global management conference I was helping make happen. Over the course of those few days, in casual conversation in his suite, seated next to him at a `formal' dinner, when just chatting as he prepped his slides on the `mac', or simply when listening to his eventual presentation, I was struck by a number of things about the great man.
Thing 1: I have never met another human being within whom the gulf between genuine modesty and actual lifetime achievements is on such a Grand Canyon-like scale.
Thing 2: Neil Armstrong isn't just a `great driver'. He's a very sharp bag of nails indeed in the cranial department.
At the dinner following his presentation, a fellow guest asked Neil "Do you believe there's life elsewhere in the Universe?" Naturally, we all waited with proverbial bated.
Bizarrely for me, yet consistent with his own tendency for self-effacement, the Columbus of our age simply put a hand on my sleeve and invited "What do you think, Brian?"
Duh. A true Homer Simpson moment in my life.
As it happened, I'd recently read Amir Aczel's `Probability1' and found the arguments therein compelling. IMHO, I tentatively offered,"It's statistically certain." Fence-sitter? Moi?
Columbus concurred. Phew.
So, let's maybe cut Mr.Cruise a bit more slack, right here, right now, O.K.,and just remind ourselves of the math supporting his `weird' belief in aliens?
Now, as far as I'm aware, the count ain't actually over yet. The polling booths are still open. But, current projections as to the number of stars in our own little galaxy tend to range from around 100 billion upwards towards 300 billion.
And estimates as to the number of galaxies within the visible Universe currently hover around the 140 billion mark.
As Bill Bryson observes in his wonderful `A Short History of Nearly Everything`, "If galaxies were frozen peas, there would be enough galaxies to fill the Royal Albert Hall", (or any Olympic Stadium you care to think of, for those for whom the venue for Eric Clapton's annual godfest is unfamiliar territory).
And to continue the analogy, if you had 140 billion - repeat billion - such Olympic stadiums and stars were themselves the size of frozen peas, you would have 140 billion Olympic stadiums each of which would be overflowing with its own hundreds of billions of frozen-pea-stars.
O.K., so let's try holding that image of 140 billion Olympic-sized stadiums, each overflowing with some two or three hundred billion pea-stars, in our minds for a moment longer?
Nice trick. Very cool. Well done.You really must show me how you did that sometime.
On y va. Now, let me quote the math, as advanced by Aczel:
" Let's start by making some reasonable and minimal (that is, most conservative) assumptions (but fully consistent with all scientific discoveries to date) about the basic probabilities of the existence of life on a planet orbiting any one star, other than the Sun.
Let's take the estimate of the number of stars with planets, as at or around p = 0.5 (some now hold this to be too conservative)
Then, let's assume that only one in nine of any such planets will lie in the habitable zone (consistent with all extrasolar planets to date discovered and confirmed in our own solar system).
Now we come to the hard part, getting a lower bound for the actual probability of life: what is the probability that DNA develops on a planet that is within its star's DNA habitable zone?
Let's entertain the notion that DNA is an extremely complex molecule with a very small chance of occurring on its own and that life is precarious because the universe is a dangerous place. Let's therefore assume that the probability of life occurring on any single planet that is already within its star's habitable zone is extremely, extremely, remote: only one in a trillion.
By multiplication of that extrmely small number by the previous factors of 0.5 and 1/9, we get the assumption that the probability of life around any one given star is 0.00000000000005.
(Slimmish, uh?)
Our galaxy has about 300 billion stars, and lets assume there are 100 billion galaxies in the universe. We can plug those numbers into our estimates and we get:
P ( the probability of life in orbit around at lest one other star in the known universe ) = 1 - (0.99999999999995) to the power 30,000,000,000,000,000,000,000,000
The `answer' is a number indistinguishable from 1.00 at any level of decimal accuracy reported by a computer. The answer is, for all practical purposes, equal to 1.00 or 100 percent.
But...
Even were we to assume that there were only 10 billion stars in our own galaxy (rather than 300 billion) and that there were only 1 billion galaxies (rather than 140 billion), the answer still comes out to a number indistinguishable from 1.00 for the probability of life elsewhere in the universe.
Finally, we really don't know for certain the size of the entire universe. Some believe that the universe is infinite. If there are infinitely many stars, the answer to our question is that the probability of extraterrestrial life is identically equal to 1.00 (not just a number indistinguishable from 1.00 to any level of computable acuracy) - and this holds true no matter how small the probability of life on any planet may be, as long as that number is not identically zero (and we know that to be impossible, since we ourselves exist)."
Got a hunch Tom and Neil would get along just fine.
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