Tip:
Highlight text to annotate it
X
Okay, Paul talked about validity in a previous video.
Uh...induction asks the question,
is an argument strong or weak?
This is still a logical issue.
It really doesn't have a lot to do
with the real world or facts.
It still has to do with a hypothetical thought experiment.
With inductive arguments,
what you want to ask yourself initially would be,
if the premise were true,
would it give me good reason to believe the conclusion?
By good, I mean better than 50% chance, but not certainty.
Only a deductive argument can give you a certainty.
So induction will make the conclusion
likely to be true, if it's working.
For instance, here, just imagine we have this argument here.
It has been sunny for the past, say, five days.
Thus, it will probably be sunny tomorrow.
Well, if it's been sunny for the past five days,
that's a bit of a pattern.
I would say it's on the strong side.
If we said, it has been sunny for the past 25 days;
thus, it will probably be sunny tomorrow.
It's an even stronger argument.
If we said, it has been sunny for the past ten million years;
therefore, it will be sunny tomorrow.
It's an even stronger argument.
But in none of these arguments do the premises
absolutely guarantee the conclusion.
Induction will never guarantee the conclusion.
They can be really good arguments.
In fact, we bet our lives on 'em on a regular basis.
Science is based on induction for the most part.
So induction's good stuff.
We don't wanna knock it down
just because it doesn't prove something,
but it acts in a different way than deductive arguments.
Deductive arguments, if they're valid,
absolutely guarantee the conclusion,
if the premises are true.
With induction, not so much.
Imagine this argument.
It has been sunny yesterday,
and therefore, it will be sunny tomorrow.
That's not so strong.
Just because it was sunny yesterday
doesn't give me good reason to believe it was sunny...
it'll be sunny tomorrow.
It has been sunny once in the past month,
and therefore, it'll be sunny tomorrow.
Pretty weak argument.
That premise does not give me
much reason to believe the conclusion at all.
It has been sunny one day this past year.
Therefore, it'll be sunny tomorrow.
Really weak argument!
So you see arguments... inductive arguments
can be very weak; kinda weak; weak; strong; very strong;
and very, very, very strong.
But they never quite get to absolute certainty
or absolute guaranteed...bad.
It's gonna be somewhere in the middle.
A little bit of this kinda gray area.
They tend to require a little more discussion,
a little more thought,
and a different kind of thought than deductive arguments.
But a different animal completely.