Archive for the ‘Certainty’ Category

Absolute certainty is elusive

December 23, 2007

You might think that all swans are white because you have never seen a black one. But there are black swans, in Australia. Karl Popper, a famous philosopher, held that even the so-called laws of science are hypothetical, subject to being disproved someday by new evidence. You only need one counterexample to disprove a claim of “never” or “always.” All swans are white — until you see a black one. But you can never tell when that will happen.Perfect knowledge is seldom if ever available to humans. For one thing, new information is constantly arriving, and human learning is constantly expanding.

While we can’t be absolutely certain, we can be certain enough to make a reasonable decision.

In the U.S. court system there are various standards of certainty. A criminal trial requires a much higher level of certainty than a civil trial to convict a person. (Consequently, an individual may be found not guilty in a criminal trial and guilty in a civil trial, e.g. O. J. Simpson).

In our everyday lives, we have to pick an appropriate standard of certainty. With trivial matters the level of certainty can be low, but for nonreversible decisions such as when choosing a spouse or a president, a much higher level of certainty is required.

Be as certain as you need to be.

Unspun by Brooks Jackson and Kathleen Hall Jamieson

Illusion of Certainty, Reality of Doubt

October 17, 2007

Humans have a “tendency to prefer the illusion of certainty to the reality of doubt.” [The Wisdom of Crowds by James Suroweicki]

In any situation we quickly become convinced that we are correct.  “This is certainly true, I am right.”

We should not be so quick in our judgments of certitude.

There are few things in life that we can be absolutely certain are true.  Even scientific “laws” are just theories that may be discarded at any time if countering evidence is found.

Best to act on your present knowledge while doubting what you know.

Best to adopt an attitude of wisdom.

If you know that you are not sure, you have a chance to improve the situation

August 17, 2007

“All scientific knowledge is uncertain”

“It is necessary and true that all of the things we say in science, all of the conclusions, are uncertain, because they are only conclusions.  They are guesses as to what is going to happen, and you cannot know what will happen, because you have not made the most complete experiments.”

“So what we call scientific knowledge today is a body of statements of varying degrees of certainty.   Some of them are most unsure; some of them are nearly sure; but none is absolutely certain.  Scientists are used to this.  We know that it is consistent to be able to live and not know.”

“If you know that you are not sure, you have a chance to improve the situation.”

The Meaning of it All by Richard Feynman