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Mini: Deductive vs. Inductive Reasoning · Why We Do What We Do

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  You're listening to Why we do what we do? Welcome to Why we do
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  what we do. I'm your host Abraham, and I'm your host Shane.
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  We are doing it. Why we do what we do? Mini talking about
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  one little topic that we can unpack and hopefully fifteen minutes or less. And
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  this is going to be a super heavy, ultra mega philosophy oriented episode in
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  fifteen minutes. Ah, yes, I think this is really interesting Personally,
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  I think most people generally have some kind of connection to philosophy, so hopefully
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  this will not feel boring to people. We're talking about deductive versus inductive reasoning,
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  so let's go ahead and start with deductive reasoning. So deductive reasoning simply
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  means that if equals B, then B equals a right. So for those
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  of you who like algebra, yeah, a way to describe that as that
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  if the premise is definitely true, then the conclusions that follow are also true.
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  So let's go ahead. Give an example. If it's true that the
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  premise that all rain falls from clouds, then it is true that it does
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  not rain where there are no clouds. That is a deductive reasoning statement.
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  Because we start with our premise, we assume our premise is true. If
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  our premise is true, then a statement drawn from that premise is then also
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  true. Right. So again, if A equals B, then B definitely
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  equals A. Right. Yeah. So Another one would be if if it
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  is true that all people name Shane have tattoos, then if I meet if
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  I meet somebody named Shane, he will logically have tattoos. So far that's
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  been true. Actually, so yeah, this is the deduction. The premise
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  is true, then the conclusion must also be true. Okay, right now
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  compared to that, And this is important in science because we're looking at in
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  science, we're trying to move from statements to make statements about the reality of
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  nature. We're moving from statements of general too specific general, like if this
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  is always true, then this statement about the nature's is definitely true. But
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  there's another way of asking questions, another way of forming statements about nature,
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  and that would be inductive reasoning. So an inductive reasoning, it's inductive.
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  If a pattern is observed, then you assume that the next pattern, the
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  next thing that will happen as a result, will will also be true.
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  And they call that another way to call it a conjecture. Right. So
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  if I find a book of a store that's on sale for fifty percent off,
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  and then another and then another, that I might expect that the next
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  one is also on sale. So you kind of just make a guess on
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  like I expect this next part of the pattern to continue. Yes. Or
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  if I observe that one kid gets better at math as an outcome of frequent,
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  repeated timed practice, and then another kid, and then another and then
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  another as I've now seen for like hundreds of iterations now, then I might
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  then conclude that the next kid will also get better at math as an outcome
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  of working on math in that particular way, right. Or if one person
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  has an extra chromosome and has specific physical and health characteristics, then another and
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  then another millions of time. At this point, I might predict that if
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  I see a child in utero. I won't because I'm not a pediatrician,
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  but if I did, then I might conclude that that child will have Down
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  syndrome, and if that extra chromosome is identified, then they will Yes,
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  Okay, So that's sort of the inductive reasoning version of things. Now.
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  A famous philosopher of old named Carl Popper, who had many things to say,
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  but one that he said is that he felt like deductive reasoning is the
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  best route for science, and that science should only do deductive reasoning, and
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  that to do so, scientists should phrase all claims as falsifiable statements, and
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  so therefore they could only ever continue to weed out things because they would only
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  ever start from a premise that entailed a conclusion. So, if all narcissists
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  lie about their failings, if you find one narcissist who does not lie about
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  their failings, then that statement is false. So that would not be a
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  good deductive statement to make. So the deduction is it is false that all
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  narcissists lie about their failings. And that was how he sort of said,
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  you could set up those deductive statements. That what I gave the example about
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  narcissist that wasn't him. Yeah, but that's how you could set up that
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  deductive statement to try and get around the problem of assuming conjecture or conclusion case,
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  engaging in conjecture about a conclusion based on the premises. He's sort of
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  saying, well, we can, we can start with a premise that can
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  only ever be falsified, and then that way we're basically never wrong. Yeah,
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  I feel like that's bad though. Well, and here's the problem.
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  The problem with all of this is that if you, I think everybody on
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  both sides of this are kidding themselves, right, because these are kind of
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  the same thing. They both start with an observation of something and then make
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  a statement about that observation. Right, So, if I observe that it
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  only rains when there's clouds, I am starting with the observation of their being
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  clouds, and then they're also being rain, and then I'm making a statement
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  about that observation. That is an inductive statement. The fact that I phrased
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  it as a premise that all rain comes from clouds is not different from saying,
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  like, because it's rained when there are clouds, I expect that it
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  will rain. It can only rain when there are clouds, Like those are
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  those are the exact same thing, right, Right, You're just phrasing one
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  in more conclusive terms than the other, like one saying, well, I've
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  observed rain coming from clouds, therefore my premises all rain comes from clouds,
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  versus saying I'm observing rain coming from clouds, therefore I'm going to look for
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  rain The next time I see clouds or if I if I am experiencing rain,
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  look for clouds right right, Like do you see? Does it make
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  sense to what I'm saying here? Yeah, I get what you're saying,
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  and I think it's I think it's also a really good explanation for why people
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  are annoyed with scientists, because it's like they're are like they argue with like
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  these like small like the wording on something is it's because to me, I
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  look at this and I go, Okay, so I could phrase it this
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  way, or I can phrase it this way, but isn't it better to
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  just say this is what we understand of our total information right now at this
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  moment. I think so, you know, like I feel like that to
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  me feels better than going I know, this would be true consistently forever,
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  you know, based on this pattern of responding. And maybe there are some
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  things that are like that, but it's not for everything. And I think
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  to isolate into a single way to maybe present a question becomes a different problem
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  too. I agree, I completely agree, and I think that yeah,
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  it's essentially we're we're arguing about arguing, you know, hey, Yeah,
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  but like there's been a lot of discussion about like in science, like you
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  have to do this deductive reasoning, and there are other people who are also
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  doing science saying no, we think that inductive reasoning is best. And I'm
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  looking at this saying like, I think that all you're doing is making statements
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  about things. Because here's I think an important understanding about this. We don't
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  know every example of anything of everything in the universe. Like, we can't
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  look at one example and say, like, we have observed every example of
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  this through all of time, throughout the entire universe. Therefore we can give
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  a general premise, right, so everything is observation and then statement about that
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  observation. Right. Otherwise we can get so specific to the point of being
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  irrelevant, you know, of like saying like, here's my scientific statement,
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  not all rain comes from clouds. So now it's like I need to go
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  find example Like, Okay, now, what's the next not question I can
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  ask if I go back to this idea of like not all people named Shane
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  have tattoos. Okay, under what condition does a Shane have a tattoo?
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  You know? Right, that's a great question. It gives us so little
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  information that we have to instead of asking general questions that we can give some
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  answers to. We have to ask a trillion, trillion trillion questions, a
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  google plex number of questions to get any idea about anything, and all we're
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  doing is weeding out bad ideas the whole time, which I mean, weeding
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  out bad ideas is a good thing to do. But like if we can
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  be more efficient with it, which is what we generally do, then I
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  think that's better. There's a point where drilling down doesn't matter anymore, right,
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  I mean, like that's kind of the thing. Is like you get
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  to a point where you're asking a question and it's getting to such I think
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  of this like baseball stats a lot, where like there's so much data right
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  now in baseball that it's like it's absurd, it's not necessary. Like you'll
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  have a batter come up and it's like, well, this is the first
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  time that somebody has bat it at seventy five degrees on a Tuesday night and
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  they've they came up with a point three to eight batting average without a doubt.
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  It's like, this is not helpful for any data analysis at this point
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  in time. It's just data for data's sake. Yeah, Right, when
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  you know how tall they are, how much they weighed the time that they
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  stepped up to the bat, how much they slept last night, how many
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  hairs are on their head, how much melatonin they have in their skin.
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  Yeah, how old they were when they were first body trained, the temperature
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  of the day, the relative humidity, the position of the sun, the
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  position of the stars, what angle they were looking at, what would their
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  be like? Yeah, you're right, Like it gets to a point of
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  just kind of ridiculous business. But here here's some examples of like deductive questions
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  where it's like, this is how specific it would get to ask a deductive
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  question. It is false that every copy of Kurt Vonicit's Cat's Cradle starts with
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  the word before on page one hundred and thirty eight. So I just grabbed
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  my book off the shelf and turn to a page, and that was the
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  first word on the page. It is false to every copy of Kurt Vontiticitt's
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  Cat's Cradle starts with the word before in page thirty eight. Okay, now
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  what do I know about that book? Nothing? Right, slightly more than
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  nothing, but so close to nothing, and it may as well be nothing.
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  Which copies don't have it, don't have it start that way? Why
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  don't they? Under what conditions should I expect it? And honestly, who
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  cares? It's drilling down too far? And I think that's the question that
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  kind of comes up when we talk about this. Does it really matter?
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  Right? Does this, any of this that we're talking about, does it
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  a week in the scientific method? Does it open the door for bad actors?
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  I mean, to me, I think that it's good to have some
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  level of structure or at least some thought about the way that we question and
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  reason stuff. But I don't know that it like, I don't know that
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  it needs to be as intentional as like a lot of folks make it out
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  to be. Like, I don't think that like we need to go in
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  go Well, you had a deductive questioning, but it should be an inductive
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  question and like you and you're doing science wrong. I don't know that it
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  matters on that level, right, But I think it's good to kind of
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  discuss it and have Like I think that's why it stays in philosophy so much.
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  Right, leave that in philosophy for the folks to kind of question and
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  ponder the ways of man I don't know that we need it as much as
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  as as maybe some people put like as much importance on it. Yeah,
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  And I think what it comes down to then is we evaluate the merit of
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  every statement, every claim, every case on its own terms. We look
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  at what are the conditions here is it's a good question to ask and why,
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  and we just evaluate it based on the context that we have available to
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  us. And I think that that will allow us to be the most efficient.
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  Really, And I think for those of you if you look up arguments,
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  you'll see something like I just watched one of these in preparation for this.
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  There's YouTube video, there's a basket, there's a cartoon. There's a
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  basket of mangos. So like, if I pull out one mango and it's
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  it's ripe, and I pull out another mango then it's ripe, then inductively
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  I conclude that if I pull out a third mango, then it's ripe.
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  Right, Okay, it might not be ripe, like it might be unripe.
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  Right, it could be possible with those right mangos in the basket.
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  Right, here's the problem with that as an example. Nobody's trying to do
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  that in science, right, No one's looking at two mangoes and assuming that
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  that tells you something about the third. What they look at is when people
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  are doing these, they look at large patterns and like, whether you call
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  that or indeductive reasoning, because they look at a large pattern, state of
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  premiss and then state of hypothesis from that premise, or they do an inductive
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  reasoning. They look at a large amount of data and then they state something
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  about that what they seem to be going on in that data. Those are
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  the same thing, right, Like, fundamentally the same thing. It's maybe
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  a slight way, maybe a slight variation in how it's worded, but it
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  doesn't affect anything in terms of what we can potentially glean from that set of
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  data. Nobody is actually doing the stupid thing where they take two examples and
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  try and extrapolate with no reason what the next example will be. It's what
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  can I synthesize from the data that I have of a aaable to me?
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  And do I state that as a general or specific premise? Right? You
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  know, right exactly, that's exactly it. Okay, So that's inductive and
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  deductive reasoning everybody. Yeah, hopefully I was helpful for you yeah, do
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  you agree? Do you disagree? I think mostly we can put this personally.
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  I think we can put this argument to bed. I think that everyone
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  is getting all up in arms about nothing and that there's no fundamental difference between
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  these two ways of going about solving something. And if you disagree, let
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  me know in the comments. You can email us directly info at wwdwwdpodcast dot
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  com. You can leave a comment or a rating and review, and if
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  you did agree with us, then hey consider supporting us. You can join
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  us on Patreon. You can pick up some merch you can tell a friend
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  all those sorts of things exactly anything I'm forgetting before we close this one out.
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  No, I think that covers it. Thank you for listening. Thank
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  you for recording with me today, Shane, Why We Do What We Do?
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  Mini is out, Ciah. You've been listening to Why We Do What
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  We Do? You can learn more about this and other episodes by going to
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  WWD ww D podcast dot com. Thanks for listening, and we hope you
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  have an awesome day.