Humanities Lectre 3 Includes info about Descartes theories
53 views2 pages
For unlimited access to Class Notes, a Class+ subscription is required.
Humanities lecture 3 - Sept 27th 2010
Anything that the senses reveal to you is always modality...and the modality is always actuality.
An empiracle claim is always subject to change --these truths are only temporal.
Decartes concludes that geometry and atirhmetic cannot be in the world but rather in the mind (we
were born with the knowledge of math ...we did not learn it)- cannot be empiracle objects because the
modality of these objects is different. These are called A-prioi (does not require any experience to know
these) --the mind has INATE objects that god has given us.
Decartes wants to adapt all learning to mathematics. In order for this to work it must be the case that
the objects that Decartes wants to study must also be inate.
A necessary connection - think of a shape... but think of this shape not existing in the world... it doesnt
work because it does exist!
pg 211 (course kit --highlighted) - sylogism --studied by aristotle. people believed that everything they
needed to know was found in aristotles book. decartes believed that it was corrupting
people...because in a sylogism the conclusion contains no new knowledge.
decartes says that we should learn discovery --the teaching of the reguli. mathematics study inate ideas
(already in the mind) and are seeking necessary connections. What the reguli will teach you is how to
discover the necessary connections that have existed.
Throughout the reguli, and parts of the principles of philosophy, decartes uses mathematics as the peridi
..--passages where decartes finds this is that mathematics is indubitable.
meditations of philosophy - pgs 48-49 -- passage
pg 220 course kit- highlighted - the reasons decartes offers for thinking that mathematics is dubitable
instead of indubitable... pg 81 in meditations helps us figure this out -bottoms of page... reason one that
math is indubitable - when mathematicians do mathematics you can raise the question with them what
is the source of your certainty? psychological irresistibality. they say - if i think of 1+1=2 ..it is
psychological. why is mathematics dubitable? ..numbers 7,5,2,.. if you add them up you get 14. ...one
will find it psychologically irrestible to know/say its 14. while you get the right or wrong answer, your
mind was forced by psychological irrestible to say what you think the answer is. ....so you cannot trust it!
.....reason # 2 - (hi-lited on pg 220 course kit) .. decartes has no knowledge of the creator but might have
been created by god. he thinks god might be tricking him. god would control your psychological
thoughts. --pont made by decartes - unless we know we were created my god, and we know that god is
not a deceiver, mathematics remains dubitable. ...reason #3 -- if you do not believe in god there are
reasons to doubt the truths of mathematics. if you believe that god created you, you must believe that