With respect to phenomena like mass extinction, somebody might say why worry about it because in a geological perspective mass extinctions aren't so bad, they wipe out some things and then 10 million years down the road we get new and interesting objects.But I tell you mass extinctions are really awful for folks caught in the midst of them.

History has got a lot to do with unique circumstances under certain particular cases and grand theories will always find counter cases. I don't think that people whose expertise lies in one thing should try to make grand theories about something (a) where it's very hard to get the evidence to prove that you're right and (b) where it's much too easy to make up stories that seem right.

I think people who worry about planetary health on geological scales are totally misguided, that's not the point at all.

Scientists are educated from a very early time and a very early age to believe that the greater scientist is the scientist who makes discoveries or theories that apply to the greatest ambit of things in the world. And if you've only made a very good theory about snails, or a very good theory about some planets but not about the universe as a whole, or about all the history of humankind, then you have in some sense accepted a lower position in the hierarchy of the fame of science as it's taught to you as a young student.

An experimental science is supposed to perform experiments that find generalities. It's not just supposed to tally up a long list of individual cases and their unique life histories. That's butterfly collecting.

In fact perhaps the only law in biology is that all flesh is mortal and all species become extinct eventually.

People who have various kinds of politics for whom it is congenial for their apriority politics to say yes, things are getting much worse. They are opposed by people who also have a priori politics saying that this is the best of all possible worlds, capitalism is the greatest thing since sliced bread and you're just alarmists and so on and they can massage the data so it fits them.