Hi Emmanuel,

well, that's the problem with natural science. They just don't ask those questions because in a biological view, they can't be answered properly. Perhaps Kant did this in a way when he said that the ability to reason is connected with their dignity. So when you say human beings are - in the biological view - just organisms with high intellectual capacity, then you might be able to say that they have the ability to reason. Some philosophers like Habermas (who is inspired by Kant) say that it is the combination of all people being vulnerable and also being able to communicate with each other on basis of reason is the starting point for morals. But that of course are again more philosophical points of view and along with it go some philosophical problems like the problem of false naturalistic conclusion. 

But I would not say, that the equality of human beings is only a religious standpoint for it is shared by many non-religious people and also in many different religions. But if you mean you have to believe in it for there is no proper scientific proof, you are right. We are talking about ethics here and natural science can't be translated directly into ethics.

I would of thought the definition of species, where two individuals can mate and produce fertile offspring (which all humans can barring fertility issues) would be a good biological basis to argue for the equality of all humans.

As noted by Martin Jungkunz nature itself and the study of nature (i.e. natural science) yield no ethical or moral value systems and no commandments how we should live or approach fellow human beings. Attempts to search for scientific justifications of ethics (without further non-scientific premisses) are considered as 'naturalistic fallacies' (sensu Moore, see also WP article http://en.wikipedia.org/wiki/Naturalistic_fallacy)

However, our scientifc knowledge about how society, ethics, law, belief systems and so on have arisen in the course of evolution can give us a certain input into the discussion of ethics. This idea is sometimes referred to as 'evolutionary ethics' and represents a classical field of discussion in sociobiology.

There is also a book - in German though - which includes different classical evolutionary biology positions as well as modern positions about these topics: Bayertz, K. (1993, ed.) : Evolution und Ethik [Evolution and Ethics]. Stuttgart: Reclam, 376 pages.

See also: https://scholar.google.de/scholar?q=bayertz+evolution+und+ethik

(Some of the citing articles are in English.)

Dear Jungkunz, Hutchins and Buchwitz,

Thank you a lot for your contributions. If we talk equality in a sense of having same essence or biological nature of our bodies, we can easily think and agree we are equal. Natural sciences also equal humans with other animals.

Evolution ethics may be considered as natural science although in truth, it is filled with many assumptions and theories that can never scientifically be proved. Historically, evolution theory has deteriorated the equality of human beings thus causing slavery and other inhuman catastrophes like holocaust.

Unless we have other way to think about human equality, can natural sciences provide clearly the basis of human equality?

Yes and no: natural sciences can only answer questions of natural science. So they can provide a basis for human equality in the sense of everbody being equal in a biological way. To deduce a moral law from that leads to the already mentioned naturalistic fallacies.

Just a word or to about evolution theory: yes, it is only a theory. But so is gravitation and no one would question it anyway. Most scientific knowledge is "only" based on theories. I also would not agree that it caused slavery and the holocaust: evolution theory -- again -- does not have a moral implication. It is a theory of natural science and has just been abused to justify immoral action. Here we can clearly see, how dangerous it can be to mix things that cannot be mixed: if you give evolution a moral value, than you are suddenly able to abuse it in that way.

Dear Emmanuel Buganga,

 I’m new to ResearchGate while poking around I came across your question. I’ve done some work on human rights and their relationship to the physical constructal law. Please find an overview in the following article:

http://www.westernfreepress.com/2016/03/13/scientific-proof-of-the-existence-of-natural-rights-found-in-the-constructal-law/

 Best regards,

Mike

Dear Michae T Takac,

Thanks a lot for that article.

I will respond to it soon.

Much reagrds,

Buganga