DESCARTES

MEDITATION 1

René Descartes 1596-1650

TROUBLED TIMES

PlaguesWitchcraftHereticsReligious warsNew worldNew scienceCopernicanism

Descartes is a mathematician

inventor of metric geometry“hence” a rationalistCartesian coordinateswants to create place for new science

METHOD OF DOUBT

IF something is uncertain (= possibly false)THEN treat it as though it were false.

NOTE WELL! The Method of Doubt does not amount to an argument that everything Descartes, or you, formerly believed is false.

Three Arguments for Doubt

1. Deceit of the senses

2. Dreaming

3. Malicious Demon

aka “Evil Demon”

Argument from Deceit of the Senses

i) Sometimes I have been deceived by my senses.

ii) Therefore: it is possible that my senses tells me falsehoods.

SO: I shall treat what my senses tell me as false. (Method of Doubt)

Dream Argument

i) It is possible that any test that shows I am awake is itself merely a dream.

ii) Therefore: it is possible I am dreaming now.

SO: I shall treat what I now experience as though it were a dream.

Malicious Demon Argument

i) It is possible for God to deceive me even about a priori truths.

ii) It is possible God allows me to be deceived about the a priori.

SO: I shall suppose a Malicious Demon is deceiving me

METHOD OF DOUBT

Has Descartes

gone too far with

DOUBT

?????