Why do you think the chance of intelligent life is a very small number? Considering we know of several million species, the chances are that we are right in the middle of the curve, and can't recognize the vastly more intelligent species the way an ant can't recognize our intelligence.

How is the number of known species correlated to the probability of life emerging? As far as we know, life emerged only once on earth, and all species evolved from a single common ancestor.

I'm talking about the chance of intelligent life, not life emerging at all, in response to the comment above.

You are basing the chance of intelligent life number on what? Reality is we have no clue what this number is.

Exactly, so we shouldn't say things like "no doubt" when it comes to the question of extra terrestrial life.