Darwin And Irreducible Complexity

In On The Origin Of Species, the work in which Charles Darwin first put forth the theory of evolution, he wrote:

“If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive slight modifications, my theory would absolutely break down.”

Had Darwin lived an additional 120 years or so, he would’ve become familiar with the compelling argument of irreducible complexity, which basically demonstrates that, indeed, there are many complex biological systems that “could not possibly have been formed by numerous, successive slight modifications.”

And I’d like to think that Darwin (unlike many of his scientific successors) would be intellectually honest enough to not just ignore the implications of such an argument.