Although we have in theory abolished human slavery recognized women's rights and stopped child labor we continue to enslave other species who if we simply pay attention show quite clearly that they experience parental love pain and the desire for freedom just as we do.

There are a lot of obstacles in the way of our understanding animal intelligence - not the least being that we can't even agree whether nonhuman species are conscious. We accept that chimps and dolphins experience awareness we like to think dogs and cats do. But what about mice and newts? What about a fly? Is anything going on there at all?

In a state therefore of great equality and virtue where pure and simple manners prevailed the increase of the human species would evidently be much greater than any increase that has been hitherto known.

There are two problems for our species' survival - nuclear war and environmental catastrophe - and we're hurtling towards them. Knowingly.

Mankind is considered (by the radical environmentalists) the lowest and the meanest of all species and is blamed for everything.

The Endangered Species Act is the strongest and most effective tool we have to repair the environmental harm that is causing a species to decline.

My childhood dreams were focused on being part of the effort to make humanity a multiplanetary species.

The very fact that we are having a national conversation about what we should eat that we are struggling with the question about what the best diet is is symptomatic of how far we have strayed from the natural conditions that gave rise to our species from the simple act of eating real whole fresh food.

Species go extinct because there are historical contraints built into a given body or a given design.

Let us beware of saying that death is the opposite of life. The living being is only a species of the dead and a very rare species.