Uncertain beliefs aren't equally likely

[Fluffy]

Recently, I have debated with a number of people who argue that if I cannot know a belief then I have faith in that belief. They argue that unless a belief is known, it is as likely to be true as every other non-known belief.

In philosophy, an argument can either be deductive or non-deductive. An argument is deductive if a person is unable to reject the conclusion whilst accepting the premises.
For example if my premises are "All men are mortal" and "Fluffy is a man" and I believe that these premises are true then I must accept the conclusion "Fluffy is mortal".

Deductive conclusions split all belief into two clearly defined categories: knowledge and not-knowledge. You can't get anything in between because either the conclusion of a deductive argument must be accepted or it must be rejected.

Non-deductive arguments only assign a probability to their conclusion. We never have to accept the conclusion of a non-deductive argument, even if we accept its premises. If I see 100 white swans, I might argue that all swans are white. This conclusion only has a chance of being correct since the 101st swan I see might be black. It is not certain.

This opens up a number of problems because it destroys the previous model of belief which deduction gave us. Compare the conclusions of the following arguments:

• I have seen 100 swans all of which are white. Therefore all swans are white.
• I have seen 1000 swans all of which are white. Therefore all swans are white.
• I have seen 10000 swans all of which are white. Therefore all swans are white.
• I have seen all swans all of which are white. Therefore all swans are white.

The last argument is a deductive argument. The conclusion must be accepted if the premise is. We can say that as long as the premise is true, the conclusion has 100% likelihood of being true.

The second argument is a non-deductive argument. The conclusion may or may not be true if I accept the premise. I'm not sure what chance it has of being true but I can say that it has more chance of being true than the first argument. I can also say that the third argument is more likely than both of them.

Non-deduction provides a scale of belief in terms of probability. At one end we have certainty or what is typically called "knowledge". At the other there is a 0% chance of our conclusion being true and then there is everything in between.

Knowledge only makes up those beliefs that we can state with 100% certainty all of which will be deductive. Given that, it seems strange to give knowledge some special status over the rest of belief since it is only one end of a scale. Knowledge has a higher chance of being true than beliefs with a 99% chance of being true and so on.

Therefore, it is important to distinguish between beliefs that are known from each other as well as from knowledge and not to assume that all beliefs that aren't known must be equally likely.

 

[Willamena]

Mankind can never make the claim to have "seen all swans," therefore if knowledge is limited to the deductive, we do not have "knowledge."

 

[Fluffy]

Mankind can never make the claim to have "seen all swans," therefore if knowledge is limited to the deductive, we do not have "knowledge."

It seems like there are some propositions that are undeniable.

For example, you might say that you can doubt that you are seeing an orange but you can't doubt that you think you are seeing an orange. Knowledge seems attainable from deduction.

However, both ways are consistent with what I posted.

 

[9-10ths_Penguin]

Therefore, it is important to distinguish between beliefs that are known from each other as well as from knowledge and not to assume that all beliefs that aren't known must be equally likely.

I agree. When you've thrown a dart at a dartboard in the dark, there isn't a 50-50 chance that when you turn the lights on, you'll see it stuck in the bullseye. We can still use a bit of critical thinking even when the outcome isn't perfectly known.

 

[Willamena]

It seems like there are some propositions that are undeniable.

For example, you might say that you can doubt that you are seeing an orange but you can't doubt that you think you are seeing an orange. Knowledge seems attainable from deduction.

However, both ways are consistent with what I posted.

Ah, but perception is the greatest uncertainty of all.

 

[Fluffy]

Ah, but perception is the greatest uncertainty of all.

What we perceive is uncertain. That we perceive is certain.

 

[Valjean]

Exactly the epistemological conundrum Descartes wrestled with. He concluded that the only fact that could be known with certainty was that of one's own existance.

In a world of uncertainty all we can do is go with the weight of evidence. Proof exists only in Mathematics. A fact is merely a theory with enough supportive evidence that reasonable people would be foolish not to accept it.

 

[Fluffy]

Exactly the epistemological conundrum Descartes wrestled with. He concluded that the only fact that could be known with certainty was that of one's own existance.

Descartes reaches the Cogito in the second meditations. He goes on to establish as fact a heck of a lot more in meditations 3-6 including the whole of reality as we perceive it, the existence of God and the duality of the mind and body. He felt all of these things were certain. He also did not believe that the Cogito was properly basic.

In a world of uncertainty all we can do is go with the weight of evidence. Proof exists only in Mathematics. A fact is merely a theory with enough supportive evidence that reasonable people would be foolish not to accept it.

In the OP, I referenced an argument where the conclusion is certain without delving into mathematics. Furthermore, a fact is not a theory established by evidence. See the quotation from wikipedia to see what a fact is.

Facts may be understood as that which makes a true sentence true. For example, the statement "Jupiter is the largest planet in the solar system" is made true by the fact that Jupiter is the largest planet in the solar system. Facts may also be understood as those things to which a true sentence refers. The statement "Jupiter is the largest planet in the solar system" is about the fact that Jupiter is the largest planet in the solar system.