What are Deduction & Induction? - Gentleman Thinker

What kinds of philosophical arguments can you construct, and what different techniques do they use?

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Assets:

[Maracujakeks]

When your professors show you videos in a posh English accent so everyone can feel more sophisticated

[chasemarangu]

0:40 induction - slight dip in music
0:55 induction is not certain - very notable dip in music
1:04 induction adjust to counter evidence + transition to different conversation - music goes up
1:25 the difference between deduction and induction is that deduction is complete - aka - "induction is incomplete"(I just deduced that) - slight drop in music

From these observations about multiple points where the video is ingenious I am going to induce that this channel is genious. Subscribed.

[Tterrible]

What I don't understand is why Sherlock claims to be good a deductive reasoning, when it's always seemed to me he uses inductive reasoning.

[francismausley]

Well done in under two minutes... “God has given us rational minds for this purpose, to penetrate all things, to find truth. If one renounce reason, what remains?” ~ Abdu'l-Bahá, Baha'i Faith

[oooo]

Really?
Deduction is Premises to definite conclusions,
while Induction is Premises to probable conclusions?

[shannonmacelli]

Thank you for this video. I LOVE IT. Such a delightful break from trying to read and interpret definitions. I will subscribe for more!

[DampeSN]

There are very few cases of pure deductive reasoning being possible in reality due to the fact that most premises that can be used for anything useful are themselves known by induction. In a sense, deduction is naive. "All men are mortal" for example, is known inductively. So the assertion that some person is mortal because of that fact is itself inductive, even if the last layer of that reasoning was a deduction. Examples of pure deduction are limited instead to statements that feature tautologies or arbitrary definitions.

2 plus 2 is 4. 4 plus 4 is 8. Therefore 2 plus 2 plus 2 plus 2 is also 8.

Planets sweep their orbits clear of small bodies. Pluto has not swept its orbit clear of small bodies. Therefore Pluto is not a planet.

I've seen white swans. I've seen black swans. Therefore both black and white swans exist.

Mammals give milk and have hair. Ants do not give milk. Therefore Ants are not Mammals.


I have yet to come across any purely deductive, that is where none of the premises are known by induction, statements that don't reduce to a tautology or "it is this way because we defined it this way arbitrarily."

[larryearlofnorthoakstreet]

How is the swan example "clearly a bad induction"? The conclusion is false, that's clear, but induction isn't about guaranteeing true conclusions. If the only evidence you have is an enormous number of white (and only white) swans, is there something unreasonable you want to point to about concluding all unobserved swans are white?

[MiniClown]

These are great, more Gentleman Thinker!

[MBarberfanlife]

Induction is a great method, but it's not perfect. Induction becomes less credible when we starting talking about the future and past; this is where the concept of "the uniformity of nature" comes in. In other words, this would be Humean induction and not a purely statistical argument.

The crucial point is this: not all inductive arguments rely on the 'uniformity of nature' presupposition. I don't know if Hume understood this. 

The swan example is indeed a bad way of reasoning inductively, so thanks for sharing that.

[denimbug]

Holy shit my teacher used this in class i didnt realize it was Abigale! nice

[athenajohnston]

This is great and very helpful, thanks!

[Thustlers]

The swan induction is almost the same as the canonball, we're drawing conclusions based on an insistent pattern of all our observations, what makes it 'clearly bad'?

[AustinOnSugar]

How do we reconcile that some premises used in deduction are obtained from induction? I can only assume "All men are mortal" can be accepted as true because it has been observed to always be the case, but isn't that in itself inductive reasoning?

Or do all deductive arguments naturally sport the addendum that "If A and B are true, therefore A-B must be true"? That would allow for discoveries against A or B (perhaps we might find out that Earl Grey was not a man at all) cancelling out the conclusion C.

[FromRussiaWithLuv]

Humans are concious

Humans are part of Existence
Therefore, Existence is concious

[noodl]

ok but this is actually entertaining content

[LucretiusDraco]

Cello suite no.1 in my opinion the best of the six good choice!

[QuthTheRaven]

most important video on the internet mayhap

[carterchambers]

Hi Olly. I love your videos. Can you do a video on Watchmen and the ideas of ethics and psychology in such.

[van_mel]

why does it make more sense with the accent