text: extraterrestrial life and math? read this and tell me what you think i have to conclude that there probably is intelligent life out there, simply on a probability basis. our galaxy contains some 200 billion stars. i'll make a conservative guess that on average, every star has, say, 3 planets around it. that puts us at 600,000,000,000 planets. we don't know how many galaxies there are for certain, but the lower estimates are around 200 billion, giving us 1.2 x 10^23, or 120,000,000,000,000,000,000,000 planets. take off 3/4 (at a guess) to account for the number of planets that are gas giants, or are otherwise totally unsuitable for life, giving us 30,000,000,000,000,000,000,000 planets. so, if we have even a 1/100,000,000,000,000,000,000 chance, or .000000000000000000000001% chance of there being intelligent life on any given planet, we'd have 900 of them. i'd set the odds considerably higher than that, so i'd say odd are that there is intelligent life out there. i agree.. it's so arrogant of us to think that there isn't life in other planets.