Rene Descartes' Cogito

Cogito, ergo sum

• “I think, therefore I am”

• created when realized many of his beliefs were actually false

• Descartes CANNOT doubt that he’s thinking → thought = clear & distinct

• model for truth

Descartes’ Project

After his journey of doubt, he went to built a theory of knowledge.

his project = erasing all his knowledge, starting from scratch and re-evaluate each belief he ever doubted

Cogito, ergo sum

• “I think, therefore I am”

• created when realized many of his beliefs were actually false

• Descartes CANNOT doubt that he’s thinking → thought = clear & distinct

• model for truth

Descartes’ Project

After his journey of doubt, he went to built a theory of knowledge.

his project = erasing all his knowledge, starting from scratch and re-evaluate each belief he ever doubted

Empirical Belief

Descartes questions if our five senses are actually consistently reliable

→ dream argument

ex. room temp water feels hot after playing in the snow

Dream Argument

• we can’t tell if we are awake or asleep

• we may be dreaming or believing we are awaking

further argues that medicine & physics depend on perception but mathematics don’t so those are reliable

Local doubts

the ability to check in with yourself & figure out what you’re experiencing a deception; basically doubting a particular sense in a particular point in time

Evil Genius

God could have created a demon to deceive me

Foundational Belief

at bare minimum, you known you are an entity, a mind having thoughts despite doubting everything else

first belief he regained → more perceptions he experienced made his certainty of his existence grow stronger