Evolution is a fact, as securely established as any in science, and he who denies it betrays woeful ignorance and lack of education, which likely extends to other fields as well.

Nature is not cruel, only pitilessly indifferent. This is one of the hardest lessons for humans to learn. We cannot admit that things might be neither good nor evil, neither cruel nor kind, but simply callous-indifferent to all suffering, lacking all purpose.

The total amount of suffering per year in the natural world is beyond all decent contemplation. During the minute that it takes me to compose this sentence, thousands of animals are being eaten alive, many others are running for their lives, whimpering with fear, others are slowly being devoured from within by rasping parasites, thousands of all species are dying of starvation, thirst, and disease. The universe that we observe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil, no good, nothing but pitiless indifference.

The truly adult view [...] is that our life is as meaningful, as full and as wonderful as we choose to make it. And we can make it very wonderful indeed.

For centuries the most powerful argument for God's existence from the physical world was the so-called argument from design: Living things are so beautiful and elegant and so apparently purposeful, they could only have been made by an intelligent designer. But [Charles] Darwin provided a simpler explanation. His way is a gradual, incremental improvement starting from very simple beginnings and working up step by tiny incremental step to more complexity, more elegance, more adaptive perfection.

If you want to do evil, science provides the most powerful weapons to do evil; but equally, if you want to do good, science puts into your hands the most powerful tools to do so

It would be intolerant if I advocated the banning of religion, but of course I never have.