Thursday, November 6, 2014

545: Inductive reasoning....

In the previous lecture we talked about Aristotle’s ideas about scientific inquiry: the inductive - deductive procedure, as is shown in the diagram here next to me.

From observations to principles and from principles to observations. We are so used to this procedure that it might look too obvious.

From a cognitive point of view, I would say, that you see a kind of inductive reasoning in many organisms. 

It is the ability to learn from past experiences and then come to the conclusion: RUN !!! , for instance. But that is about it. 

An animal will never think about its conclusions and reason: why always running? Maybe I just should move to a saver area.

Homo sapiens does, however. Aristotle did and his conclusions had a great impact on how we think, or maybe thought, about science.

It is easy to say, that we start with observations, but that implies that we first have to answer the question; WHAT IS there to observe?

According to Aristotle, every particular thing is a union of MATTER and FORM. Matter is what makes the particular a unique individual, 

and form is what makes the particular a member of a class of similar things. To specify the form of a particular is to specify the properties it shares with other particulars.

Matter makes something to a unique tree, but specifying the properties it has, leaves of a certain shape, specific fruits, tells us that is has the form of an apple tree.

Aristotle maintained that it is by induction that generalizations about forms are drawn from sense experience. 

He discussed two types of induction. The two types share the characteristic of proceeding from particular statements to general statements.

The first type of induction is simple enumeration, in which statements about individual objects or events are taken as the basis for a generalization about a species of which these objects are members. 

Or, at a higher level, statements about individual species are taken as a basis for a generalization about a genus.

For instance, we observe small hairy animals of different colors, which purr, meow, are tame and Aristotle concludes that they belong to the species: domesticated cat.

The cats have properties in common with tigers, lions, pumas and the like which thence seem to be family of cats. In other words, there is a genus of felines.

With these concepts of matter and form Aristotle in fact organized our scientific way of looking at nature, like he also taught how to bring order in the multitude of observations.

In an inductive argument by simple enumeration, the premisses and conclusion contain the same descriptive terms. A typical argument by simple enumeration has the form:

a1 has property P
a2 has property P
a3 has property P
All a’s have property P.

The second type of induction is a direct intuition of those general principles, which you recognize in a particular object or event.

This is meant: you are in the jungle and see an unknown plant. Never seen before, but you are a gifted botanist. You almost directly “see” to what species and genus this till now unknown plant belongs.

It is probable that when Aristotle wrote about intuitive induction, this is a sort of “vision” he had in mind. 

Aristotle himself was a highly successful taxonomist who undertook to classify some 540 biological species.

The taxonomist is a scientist who has learned to “see” the generic attributes and differences of a sample. 

There is a sense in which the taxonomist “sees more than” the untrained observer of the same sample.

This all looks like a very promising approach of scientific inquiry. Aristotle’s message was: use your senses, look at nature and observe, 

or as we would say it today: gather as many data as possible about the subject and find the explanatory principles.

The Discussion

[13:20] herman Bergson: Thank you... ^_^
[13:20] Gemma Cleanslate: that was not so bad
[13:20] ZANICIA Chau: Thank you Herman
[13:20] herman Bergson: Glad you say so, Gemma :-)
[13:20] Bejiita Imako: ah
[13:20] Ciska Riverstone: thank you herman
[13:20] Nymf Hathaway: Thank you Herman
[13:21] Dawn Rhiannyr: Thank you Herman :)
[13:21] Bejiita Imako: indeed basically this is how science work today i guess
[13:21] Bejiita Imako: through this principle and then to classify things based on properties
[13:21] herman Bergson: Yes Bejiita that is what we are inclinded to believe.
[13:22] herman Bergson: In the coming lectures you'll see that  there are other views these days
[13:22] Bejiita Imako: a CERN example would be the group Hadrons, hadrons are all articles made of quarks and quarks in turn belong to their own group and so on
[13:22] Dawn Rhiannyr: sorry I have to leave :( thank you Herman
[13:22] Bejiita Imako: based on properties and how they look
[13:22] Gemma Cleanslate: and science saved your life
[13:22] herman Bergson: ok Dawn...
[13:22] Nymf Hathaway: Waves at Dawn
[13:22] Bejiita Imako: bye dawn
[13:22] Gemma Cleanslate: Bye, Bye   
[13:22] Gemma Cleanslate: dawn
[13:22] herman Bergson: We will get to CERN too Bejiita :-))
[13:23] Bejiita Imako: same that example with plants
[13:23] Bejiita Imako:
[13:23] herman Bergson: Not yet now, but in coming lectures
[13:23] Bejiita Imako: everything can be put into a group
[13:23] Bejiita Imako: the thing is to define this group properly
[13:23] herman Bergson: But there is a flaw in Aristotle's approach....didn't you notice? :-))
[13:23] Gemma Cleanslate: well
[13:23] Bejiita Imako: hmm ok
[13:24] ZANICIA Chau: ?
[13:24] herman Bergson: Even in common sense talks you point at it now and then
[13:24] Gemma Cleanslate: back at the x1 and x2
[13:24] Gemma Cleanslate: etc
[13:24] herman Bergson: Go on Gemma :-)
[13:24] Gemma Cleanslate: seems 3 examples are not enough
[13:24] Merlin Saxondale: Oh I wondered about that
[13:24] Gemma Cleanslate: too much generalization
[13:24] Gemma Cleanslate: so far
[13:24] Merlin Saxondale: I did not like to be picky and I thought it was just an example
[13:24] Bejiita Imako: aaa yes that is true
[13:25] herman Bergson: Ok many examples would be enough
[13:25] Bejiita Imako: as we say in Sweden, draw all over one comb
[13:25] Gemma Cleanslate: unless he corrected it else where
[13:25] Gemma Cleanslate: depends
[13:25] herman Bergson: Exactly Bejiita
[13:25] Bejiita Imako: just because 3 are green doesn’t mean all are green
[13:25] Merlin Saxondale: There is no number which is sufficient
[13:25] Gemma Cleanslate: it is the information about x1 and x2
[13:25] herman Bergson: Indeed Merlin.....He uses the quantifier ALL in his conclusion
[13:26] Gemma Cleanslate: etc
[13:26] herman Bergson: and that is questionable....
[13:26] Bejiita Imako: ah
[13:26] Gemma Cleanslate: was that the part you mean we should question
[13:26] herman Bergson: We'll get back to this issue more often in the future...
[13:27] herman Bergson: Yes Gemma, because  by finding new samples of some thing you yet never reach all samples...
[13:27] ZANICIA Chau: Darwin would have questioned, as he believed in challenging 'absolutes'.
[13:28] Ciska Riverstone: the plant for example could match in 20 points the group the specialist knows but not in 2 which are not viewable on first sight and give an other origin by a closer look 
[13:28] herman Bergson: Induction never leads to absolute "All....A are B " conclusions
[13:28] Merlin Saxondale: Cantor would certainly not have liked it!
[13:28] herman Bergson: Yes Ciska, that is why some taxonomies are revised now and then
[13:29] Bejiita Imako: we wil always discover new things so generalization can be a really bad thing to put in
[13:29] Gemma Cleanslate: of course we have to remind ourselves of the state of science in those days too
[13:29] herman Bergson: We make mistakes....
[13:29] Bejiita Imako: yes
[13:29] Nymf Hathaway: Thank you Herman, I am sorry but I need to leave too :( Thank you again
[13:29] Bejiita Imako: bye chantal
[13:29] ZANICIA Chau: Me too. Sorry
[13:29] herman Bergson: Induction bring us to "It is probable to a certain extend that all....."
[13:29] Nymf Hathaway: Bye bye enjoy everyone!
[13:29] Nymf Hathaway: everyone too
[13:29] Ciska Riverstone: take care chantal
[13:29] Bejiita Imako:
[13:30] MikkiLouise: the important thing surely is to recognize the imperfection of a classification and not be afraid to revise when new data is presented. This defines proper science.
[13:30] herman Bergson: My goodness....this lecture is wearing down people, it seems :-))
[13:30] Bejiita Imako: a good example is definition of salts
[13:30] herman Bergson: Indeed Mikki
[13:31] Bejiita Imako: at first we thought it had something to do with oxygen byt after many redefinitions we finally arrived at the ionic compound theory
[13:31] Bejiita Imako: that proved true
[13:31] Ciska Riverstone: which might not be the last station either Bejiita ;)
[13:31] herman Bergson: This is another point...this matter - form idea of Aristotle...
[13:32] Bejiita Imako: well we now know for ex that common salt is sodium and chloride ions and they are produced from a neutralization reaction
[13:32] herman Bergson: I didnt know that :-)
[13:33] Bejiita Imako: mix caustic soda (sodium hydroxide) and hydrochloric acid and u end up with salt water
[13:33] Bejiita Imako: common chemistry class experiment
[13:34] herman Bergson: Well, I guess that you all understood that INDUCTION is an important way of reasoning in science, but that it also entails a number of serious questions
[13:34] herman Bergson: We'll deal with those often in future lectures...
[13:35] Bejiita Imako: this can be good
[13:35] herman Bergson: So, let's keep it to that for today unless you still have a question....
[13:35] herman Bergson: ok...then...thank you all again for your participation...
[13:35] Bejiita Imako:
[13:35] herman Bergson: Class dismissed... ^_^
[13:35] Bejiita Imako: great class again
[13:36] Bejiita Imako:
[13:36] herman Bergson: thank you Bejiita
[13:36] Ciska Riverstone: thank you herman thanx folks
[13:36] Beertje Beaumont: yes very interesting:)
[13:36] Beertje Beaumont: thank you Herman
[13:36] Bejiita Imako: cu soon again
[13:36] herman Bergson: You will Bejiita :-))

[13:36] Bejiita Imako:

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