"Mystery, as such, is no bad thing. Pointing out mysteries can be a valuable exercise—firing up our curiosity and getting us to engage our intellects. Nor is there anything wrong with acknowledging that some things may forever remain a mystery, and might even be in principle unknowable.
Sometimes it’s also reasonable, when faced with a problem case for an otherwise well-established theory, to put it down as a mysterious anomaly. If on countless occasions an experiment has confirmed water boils at 100 degrees C, the fact that on one occasion it appeared not to may quite reasonably be put down to some unknown factor. If we can’t discover what went wrong, it can be reasonable to just shrug and move on—putting the freak result down to some mysterious problem with the set up (a faulty thermometer, perhaps).
It’s also often reasonable, when we have a theory that works but we don’t fully understand why it works, to say, “Why this happens remains, for the moment, a mystery. But we know it does.” We might have strong evidence that smoking causes cancer, say, long before we understand why it does so.
So the appeal to mystery has its proper place, even in science. What I object to is the way in which the appeal to mystery is increasingly relied on to deal with what would otherwise appear to be powerful evidence or arguments against certain beliefs, particularly beliefs in the supernatural. Whenever mystery is erected as a barrier to rational inquiry, a barrier that says, “You scientists and philosophers may come this far armed with the power of reason, but no further—turn back now!” we should be concerned, particularly if no good reason is given for supposing science and reason cannot, in fact, take us further. The more we appeal to mystery to get ourselves out of intellectual trouble—the more we use it as a carpet under which to sweep inconvenient facts or discoveries—the more vulnerable we become to deceit: deceit by both others and by ourselves."

"Your brain is built of cells called neurons and glia—hundreds of billions of them. Each one of these cells is as complicated as a city. And each one contains the entire human genome and traffics billions of molecules in intricate economies. Each cell sends electrical pulses to other cells, up to hundreds of times per second. If you represented each of these trillions and trillions of pulses in your brain by a single photon of light, the combined output would be blinding.
The cells are connected to one another in a network of such staggering complexity that it bankrupts human language and necessitates new strains of mathematics. A typical neuron makes about ten thousand connections to neighboring neurons. Given the billions of neurons, this means there are as many connections in a single cubic centimeter of brain tissue as there are stars in the Milky Way galaxy.
The three-pound organ in your skull—with its pink consistency of Jell-o—is an alien kind of computational material. It is composed of miniaturized, self-configuring parts, and it vastly outstrips anything we’ve dreamt of building. So if you ever feel lazy or dull, take heart: you’re the busiest, brightest thing on the planet."