h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I think I may finally be getting a handle on the Zen principle of avoiding duality. Yesterday I heard Tuvok say to Kes "To understand the light, there has to be dark, for without the dark, how can you recognise the light?"

Why does one need to be able to recognise the light? If it's there and if it serves its purpose, does it need to be acknowledged and understood? Can it not be just accepted? I thought that "acceptance of what is" was a fundamental Vulcan priciple. If you can do the Buddhist thing of "becoming one with the {whatever}", you can understand its very essence, so you don't need its opposite to be able to know it.