"I have often been asked how it happens that I neither drink nor smoke. My answer is that both liquor and tobacco have their uses, but I am of a nature that has never required a stimulant or a sedative. As a scout, I needed all my five senses and every faculty of my mind at highest efficiency at all times. There is nothing that sharpens a man’s senses so acutely as to know that bitter and determined enemies are in pursuit of him night and day. 

In many lines of endeavor, errors may be repeated without fatal results, but in an Indian or savage war, or in a bitter feud, one little slip entails the “absent” mark forever against a man’s name. I recall one scout who forfeited his life by his neglect for one instant to keep in the shade of a small oak tree. He was safe from sight so long as he kept in the shadow, but he became so intent on using his field glasses that he allowed a shaft of sunlight to betray him to the enemy. 

The senses and actions of every animal, bird, and insect, if studied, can be made to pay tribute to our store of human knowledge, and our own rather dull wits can be wonderfully informed. Solitude intensifies the perceptions. The herd with a thousand eyes trusts itself to a solitary sentinel with only two." (Frederick Russel Burnham)