Parasites are Always Out There, Waiting

But however secure and well-regulated civilized life may become, bacteria, Protozoa, viruses, infected fleas, lice, ticks, mosquitoes, and bedbugs will always lurk in the shadows ready to pounce when neglect, poverty, famine, or war lets down the defenses.

 Humanity is Like an Infant

Taking a very gloomy view of the future of the human race, let us suppose that it can only expect to survive for two thousand millions years longer, a period about equal to the past age of the earth. Then, regarded as a being destined to live for three-score years and ten, humanity although it has been born in a house seventy years old, is itself only three days old. But only in the last few minutes has it become conscious that the whole world does not centre round its cradle and its trapping...