What Makes Us Human?

Moral thought has come a long way in the course of history, and has now settled mainly on humanitarianism, the idea that all humans are equal, priceless, and deserve a helping hand. But moral philosophy is far from finished. For example, if we find intelligent alien civilizations, we will have to extend our humanitarian values to include them as well. Possibilities like this raise the question, what makes humanity special?

On the surface, we might think it obvious. There are many things we can do that no other living thing on earth can. The philosopher Aristotle said that man is the rational animal. We can reason. We can write poetry. We can paint pictures. Perhaps it is a combination of all these things. In the sci-fi novel Out of the Silent Planet, by C. S. Lewis, there are three intelligent species, developing side-by-side with each other. Because of this, they came up with a word to call themselves, to differentiate them from the animals: hnau.

But while there may be obvious differences in our everyday life, there is no guarantee that there will always be. In fact, there was a time in the past when it was not. Around 50,000 years ago, the line was blurry when Homo sapiens and Homo neanderthalensis shared the planet. Before that, there were other species of proto-humans, who used tools and had advanced social structures. And before that, there were only creatures of the level that we now consider to be animals. The transitions between these stages were astronomically slow, taking much longer than our entire recorded history. In light of this, we must face the fact that humanitarianism is unstable.

There was a time when a few proto-humans began to speak, and eventually language spread over all people and became the norm. Similarly, throughout the past several thousand years, we see a few humans learning not from tradition but from logic and observation. And now, such thought is spreading around the world. It is theoretically possible for those of us who think more sophisticatedly to separate from the others and evolve into a new, more intelligent human species. Would they, then, have the right to subjugate the others? Absolutely not! But why? If not because we are the same species, then what?

And with species not being the boundary, do we have obligations regarding the treatment of animals, as philosopher Peter Singer claims? If so, how far down the animal ladder should we go? We obviously cannot worry about accidentally stepping on insects, and we kill bacteria every time we sneeze. Almost everything we eat was alive at some time. If we thought it wrong to harm any life at all, the least evil thing we could do would be to kill ourselves!

We also need to face the fact that, even when it comes to human intelligence, there is plenty of room for improvement. There could easily be races out there that are as far beyond us as we are beyond the smartest animals. Popular science communicator Neil deGrasse Tyson has a hypothetical scenario, based on the fact that we can teach chimpanzees a few rudimentary words in sign language, and to do tasks at about the level of a four-year-old human. Suppose we meet an alien race advanced enough to find and visit us. We want to show off our achievement as a species, so we bring our smartest, Stephen Hawking, before them. The aliens say, “he can do astrophysical calculations in his head? That’s cute, just like our little Timmy.”

An ant has no quarrel with a boot.

How is the value of a life defined so that we don't have to feel bad stepping on insects, but it would be wrong for god-like aliens to tread on us? Though species can’t be the only condition, it must be important, or else it would be possible that not all humans would count. One additional condition might be that a creature deserves humanitarian treatment if one or more of its species has the capability of contemplating its own death. This would mean it has sufficient rationality to understand how it is being treated, and become indignant if a more intelligent race comes along and wants to use it as a beast of burden, raise it for food, or exterminate it.

And no conversation about the essence of humanity would be complete without mentioning artificial intelligence. Would an intelligent being created by scientists, such as Star Trek’s Data or holographic doctor, warrant ethical treatment? It would seem to me that it shouldn’t matter how someone comes into existence if they have the capabilities to make decisions and have conscious experiences, but how would we know if such a being is actually alive, or if it is just well-programmed to mimic life?

The question of why humans are special is deeply important to every part of our existence. I don’t know the answer. Perhaps as science continues to probe the mystery of consciousness, it will unearth more clues to solving this puzzle. It is a topic I find fascinating, and you can bet I will explore it in the novels I write.