Here’s a practical way to improve your rational thinking.

How fast do you have to drive to average 60 mph across a one mile bridge if you drove 30 mph on the first half? 90 mph?

No, it’s impossible, because you ran out of time driving the first half.

Even rational thinkers can fail to take into consideration all the relevant real constraints when solving problems. Frequently, time is ignored. Rational thinkers can also suffer from ‘analysis paralysis’ when they spend too much time gathering information and thinking without reaching a conclusion. Ignoring the limits of the real world results in elaborate fantastic theories, instead of solutions.

A common mistake, even among the well-educated, is to believe infinity is real. This leads to a lot of nonsensical beliefs and mistaken thinking. 2,500 years ago, a Greek philosopher named Zeno mocked the mathematical concept of infinity as failing to apply to the real world.

• If an arrow is not moving at any specific moment in time (i.e. an infinitely small increment of time), then it is stopped and not moving. How does it continue?
• If you have to reach the halfway point before you catch up to the slower runner ahead or reach the end of the race, then there will always be half the distance remaining if you calculate an infinite number of times.

Infinity is not real. Even when the concept is presented in calculus, it is simultaneously presented with the concept of a limit. That means that even the mathematical construct of infinity, designed to solve theoretical math problems, is limited. Take the infinitely repeating decimal 0.99999…. Your math teacher may have claimed that it was equal to 1, perhaps using a phrase like “for all intents and purposes”. But the only way that could be true, is if infinity is limited, which contradicts the meaning of infinity. Sure, it’s useful in math, but nothing in the real universe is infinite.

All matter and energy is limited to travel no faster than the speed of light, which is a measurable constant. There is a finite amount of matter and energy in the universe, expanding at a known rate over a known period of time. The universe is undoubtedly larger than humans will ever know, but it is not infinite. If there were an infinite amount of gold, then there would be gold everywhere. If there were an infinite amount of intelligent alien species, who could travel faster than the speed of light, then they would visit Earth every day of the week. If there were an infinite number of multiverses, then no less than one of them would contain a magical version of yourself who would instantly appear before you to disprove what I am writing now. It’s all imaginary nonsense.

The problem here is that humans have an instinctual fear of death, so we imagine an infinite universe or multiverse, which would allow for everything, everywhere, all at once. We hope to be reincarnated in an infinite future, to live forever in some afterlife set in a different dimension, or that there’s some alternate reality where our lives and our species do not end in death. Rather than take responsibility for our fragile existence and the real consequences of our fatal mistakes, we waste time dreaming about imaginary friends and foes, worlds better and worse than our own. How childish and irresponsible.

Rational thinking should be used to solve real world problems, within real constraints, such as limited time, resources and budget. Economic theories may point the direction, but since they contain unrealistic assumptions, they will not solve all real problems. Rational thinking requires real world accuracy. There will never be enough time or resources to solve every problem perfectly, but what time and resources we have to solve important problems should not be wasted on fanciful notions, daydreams or wishful, unrealistic thinking.