Being pure is supposed to be a good thing, and I guess sometimes it is. But sometimes it isn’t Having pure air to breathe or pure ingredients to work with are universally seen as good. But in other, more abstract contexts,  the idea of purity cab be a dangerous myth. A good example is the idea of a pure race. There is, in fact, no such thing anywhere on Earth. Genetic studies have shown that isolated populations once thought to be unmixed with other human groups, such as Icelanders or Japanese, are nothing of the kind. They all show the normal degree of genetic interbreeding with other population groups found in all Asians, Europeans and Africans.

In politics the concept of purity has been deadly and a force mostly for evil. In the early part of the last century, ideological purity led communists to massacre socialists and anarchists because of their failure to adhere to the pure doctrines of Stalinism. The same kind of purging of anyone who deviated at all from the true pure path was done by the fascists and Nazis during their rise to power and their march to destruction.

In fact, if we think of purity as the opposite of diversity (as it is), it isn’t hard to see that there isn’t much good about purity when it comes to human politics or sociology. Purity of thought is a particularly dangerous notion in our modern political arena. On both the left and the right, there is a possibility that committed ideologues will pursue their heartfelt certainty of being absolutely right, to the extent of limiting diverse opinions that might clash with fundamental tenets of their worldview. This is not a good characteristic to have in a leader of an extremely diverse nation.

What about in science? Certainly in science there are pure truths, and all scientists agree on what is true and what isn’t? The answer is no, scientists rarely agree on what is true and what isn’t, because the idea of pure scientific truth is as mythological as that of pure races. This isn’t to say that there are no well-established facts. The validity of the law of gravity or the reality of evolution, for example, have both been demonstrated thoroughly. But that’s only the first step in science. Knowing how evolution works, or how gravity fits in with other aspects of the physical world, like quantum mechanics, are questions with quite of bit of diversity of views.

Diversity of opinion is not only welcome in science, it is the vital engine for scientific progress. Purity is the enemy of science, as it is the enemy of religion. Yes, purity is the enemy of faith, because our understanding of God and His purposes and works requires just as much diversity and creative ideas as does progress in science. If you object that religion is dogmatic and doctrinal by nature, you haven’t been paying attention. Remember that a favorite atheist argument against religion is that since there are so many of them, how can we tell which one is right? The reason there are so many varieties of Christian faith, for example, is that people’s  religious ideas and practices are naturally diverse, and many great minds  have rebelled against stifling and rigid purity of thought.

So I am not a fan of purity at all. I like the impurities of diversity much more. Whether it is the shapes and colors of people, the way we think, the kinds of plants and animals that inhabit our world with us, the way we do things, or the way we worship, I am not interested in purity. Let’s have pure water, pure soap, and pure hearts, and leave it at that.