# How Hugh Ross Calculates the Improbability of Life on Earth due to Chance Alone

As someone who knows a thing or two about probability, I’ve always wanted to dive into the technical details for how proponents of cosmic fine-tuning arguments justify the probability estimates associated with such arguments. Along those lines, I just found this page on Hugh Ross’s *Reasons to Believe *website:

Probability for Life on Earth (APR 2004)

Ross arrives at the conclusion that the probability of life on earth, conditional upon the hypothesis that it arose by chance alone, is 1 in 10^{282}.

I may eventually write up my own thoughts on his calculations, but in the meantime consider this post an exercise for the reader. 🙂 What do you think?