Readers say scientists can, indeed, knock on heaven’s door

The statement by Keith Schofield that “we have no theory … on the biggest question: how life originated” needs correction. Quite the contrary, we have and continue to develop such theories. They have led to a variety of experimental and analytical approaches that have yielded steady, if slow, progress in understanding that very fundamental problem. Undoubtedly, some theories are dead ends, but that does not mean that improved understanding is...