Be careful about making assumptions

Your assumptions are your windows on the world. Scrub them off every once in a while, or the light won’t come in.
—Isaac Asimov

Assumptions—we can’t function without them, but sometimes they mislead and get us into trouble. Often they are based on sound evidence and are helpful, providing order and predictability. But sometimes they are built on false premises in which case they can jeopardize critical thinking and good judgment. At their worst, assumptions are the lowest form of knowledge.

Some assumptions are helpful: I assume my house will be standing when I get home tonight; I assume my heart will keep beating; I assume my bank will accurately handle my checking account. Without the aid of basic assumptions, we would constantly be anxious, obsessive, and distracted. But we often imperil wise living when we think, “I just assumed…”

Here are some ways to analyze assumptions and separate the good from the bad.

Consider the importance of every action; the more critical the action and its consequences, the more dangerous assumptions can be.

  • I assume my car is going to start in the morning, but if my first appointment of the day is a critical job interview, I’m going to have a backup plan.
  • If I’m teaching a workshop at an unfamiliar venue, I should not assume my computer will work with the venue’s projector. I better test it the day before my workshop, because if it doesn’t sync properly, the result could be disastrous.
  • I’m depending on my friend to take me to the airport. I can assume he remembers, but I would be wise to confirm the arrangement because if my assumption is wrong, I’ll miss my flight.

Consider what the probability is of each assumption being accurate; the higher the probability, the more secure you can be in acting on the assumption.

  • I assume that the sun will rise in the morning.   [99.999999999% probability]
  • I assume that the drinking water in a developed country is purified.   [97% probability]
  • I assume my flight will leave on time. [78% probability]
  • I assume that the soap dispenser in a public restroom will work. [33% probability]

Consider the source of information and evaluate its trustworthiness.

  • An unknown mechanic tells me that I need $1,000 worth of repairs to my car. Should I assume he’s telling me the truth?
  • The office rumor-mill says that layoffs are imminent. Should I assume the rumors are true?
  • My doctor tells me my blood pressure is high. He’s a terrific physician so I assume he’s correct. Why would he lie?

Don’t embrace unsubstantiated thoughts, particularly when they are tied to critical consequences. Trust in facts and evidence.

If we don’t scrutinize our assumptions, we’ll live naively and suffer for it.
If we disallow all assumptions, we’ll be unduly paranoid and anxious.

Find the right balance.

This sweet girl made the wrong assumption. I’m glad she wasn’t hurt.

[youtube id=”8fChBzt-fyA”]

[reminder]What are your thoughts about this essay?[/reminder]


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6 Replies to “Be careful about making assumptions”

  1. That has to be your best essay to date and that’s a very high bar! Always learn something from you, Don.

  2. When a person relies on unscrutinized, unsubstaniated assumptions they are in danger of committing “assuma-cide”: the unfavorable result of faulty expectations. In the case of the video, both girls committed assumacide!

    1. I like your term “assumacide” because it underscores the danger of unsubstantiated assumptions. Thanks, Paul.

  3. Great article, Don. One further thought I have is the real harm caused by assumptions made regarding a person’s looks or actions. When a misguided person makes an assumption about that person being dangerous and it appears on social media, it severely damages that person’s reputation and causes much fear and anxiety in others who believe such assumptions to be true. Paul’s “assuma-cide” is a wonderful description–think I’ll use it here on the island and of course attribute it to Paul.

    1. Kendel, Thanks for sharing your thoughts. You’re right, words can harm, particularly in this age of social media. Don

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