Many people are cautious, some to the point of cowardice, the type who, in the words of the actor Victor Mature, "wouldn't walk up a wet step." Caution, within reason, is only natural. As Dr. Kenneth Kamler wrote in Surviving the Extremes, "no animal in its right mind ever intentionally puts itself in danger by going somewhere it doesn't belong." Yet, as Kamler notes, human beings do go where they don't belong, for example into the 8,000 m (26,246 ft) "death zone" of Mount Everest. He suggests that human "e