Many atheists are very moralistic. They quote passages from the OT which they find morally outrageous. They wax indignant at the political agenda of religious right.
They fervently believe in human rights, and they feel that the Bible and Christian ethics infringe on human rights. But where is all this coming from?
Before we can ask what rights (if any) a human being has, we need to ask what a human being is. From a strictly naturalistic viewpoint, what does a human biological unit amount to?
From an evolutionary perspective, human life arose from inorganic chemical reactions. Indeed, our bodies are still reducible to inorganic compounds.
Then there’s the big picture view of human organisms. Where we fit in the ecosystem. Our ecosystemic role is to metabolize carbohydrates, lipids, and proteins. Basically, we’re glorified digestive systems. From an ecosystemic standpoint, the most important part of a human unit is the gastrointestinal tract. Intake and outtake. Ingestion and egestion. In one end and out the other. We thereby help to maintain the balance of nature by breaking down and oxidizing large molecules. That’s a necessary link in ecosystemic ecology.
Of course, a digestive system can’t exist in isolation. It can only function in a living body. Our hands and feet, heart, lungs, brains, &c., are aids to the digestive system. They keep it alive and functional. They enable us to acquire the raw materials.
Human units age. So we reproduce our replacement units. The survival of the ecosystem is not contingent on the survival of any individual human unit. The ecosystem has great redundancy. Human units are highly expendable and disposable.
Our value isn’t essentially different than the value of an earthworm, which also contributes to the ecosystem by converting dead organic matter into humus. Or trees, which emit oxygen and filter carbon dioxide.
We’re important in relation to the ecosystem. Of course, from a naturalistic perspective, the ecosystem has no inherent value. It simply is. The result of fortuitous initial conditions. When our sun burns out, the biosphere will die.
From a naturalistic viewpoint, humans are processing systems–like sewer plants.