In one more example, you learn that a species of unwanted algae is spreading on the surface of your favorite pond. The growth is persistent and doubles in area every day. After a month, the lake is half-covered in algae. At this rate, how much longer until algae covers the entire lake? Our primitive, linear brain calculates “one month.” But the actual answer is “one day.” Doesn’t even matter how long it took for the pond to become half-covered. If the rate of coverage doubles every day, you can be sure that when it’s half-covered, you’ve got just one day left.
