Star Trek’s Mr. Spock is not the exemplar of logic and rationality. Instead, he is a “straw man” of rationality used to show that human emotion and irrationality are better than logic.
His role is to show that emotion and irrationality is superior. He gives extremely exact probabilities which never pan out.
"The spatial anomaly has interacted with the tachyonic radiation in
the nebula, it's interfering with our sensors. It's impossible to get
"There's no time - we'll have to take the ship straight through it!"
"Captain, I advise against this course of action. I have calculated
the odds against our surviving such an action at three thousand, seven
hundred and forty-five to one."
"Damn the odds, we've got to try... wait a second. Where, exactly, did
you get that number from?"
"I hardly think this is the time for-"
"No. No, fuck you, this is exactly the time. The fate of the galaxy is
at stake. Trillions of lives are hanging in the balance. You just
pulled four significant digits out of your ass, I want to see you show
your goddamn work."
"Well, I used the actuarial data from the past fifty years, relating
to known cases of ships passing through nebulae that are interacting
with spatial anomalies. There have been approximately two million such
incidents reported, with only five hundred and forty-two incidents in
which the ship in question survived intact."
"And did you at all take into account that ship building technology
has improved over the past fifty years, and that ours is not
necessarily an average ship?"
"Indeed I did, Captain. I weighted the cases differently based on how
recent they were, and how close the ship in question was in build to
our own. For example, one of the incidents with a happy ending was
forty-seven years ago, but their ship was a model roughly five times
our size. As such, I counted the incident as having twenty-four
percent of the relevance of a standard case."
"But what of our ship's moxie? Can you take determination and drive
and the human spirit into account?"
"As a matter of fact I can, Captain. In our three-year history
together, I have observed that both you and this ship manage to beat
the odds with a measurable regularity. To be exact, we tend to succeed
twenty-four point five percent more often than the statistics would
otherwise indicate - and, in fact, that number jumps to twenty-nine
point two percent specifically in cases where I state the odds against
our success to three significant digits or greater. I have already
taken that supposedly 'unknowable' factor into account with my
"And you expect me to believe that you've memorized all these case
studies and performed this ridiculously complicated calculation in
your head within the course of a normal conversation?"
"Yes. With all due respect to your species, I am not human. While I
freely admit that you do have greater insight into fields such as
emotion, interpersonal relations, and spirituality than I do, in the
fields of memory and calculation, I am capable of feats that would be
quite simply impossible for you. Furthermore, if I may be perfectly
frank, the entire purpose of my presence on the bridge is to provide
insights such as these to help facilitate your command decisions. If
you're not going to heed my advice, why am I even here?"
"Mm. And we're still sitting at three thousand seven hundred to one
"Three thousand, seven hundred and forty five to one."
"Well, shit. Well, let's go around, then."