Kindness and science

Please go over to The Huffington Post and read a little article on kindness by Susan L. Smalley, Ph.D., a Professor in the Department of Psychiatry and Biobehavioral Sciences at UCLA who specializes in the genetics of psychiatric disorders. Here's part of what it says:

I've studied genetics and human behavior for over 20 years. At one time I thought genetics held all the answers to make the world a better place by enabling us to 'fix' our genetic mutations and reduce disease and suffering. Now I see that genetics is extremely important, but for another reason: Genetics may be the best tool to provide a rationale for including kindness as a guiding principle to govern our day-to-day behaviors as well as government and institutes in general. Clearly, the thesis that we are 'all created equal' is evident in our genomes; we differ so minutely from one another. If we recognize fully that we are truly a single human family, taking it to the extreme, one could view the whole human species as a single human 'organism' based on our shared DNA. Through our shared genomes, we can see that to reduce suffering, to remove harm toward any of our members, is equivalent to removing harm toward ourselves.
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What would the world be like if it were one where kindness was its guiding principle? War would not be an answer to anything, period. We would protect the planet, animals on it, and each other at all costs. Genocide would not happen.

Why is this so hard for humanity? We've had the Golden Rule for thousands of years and it's found in all major wisdom traditions.