theory_of_knowledge.md (1937B)
1 # Theory of Knowledge 2 3 # Philoshophy 4 5 ## I think therefore I am. 6 7 René Descartes discovered certainty by doubting everything until he found 8 something indubitable: the act of thinking itself. Because he was thinking (and 9 doubting), he knew he must exist, famously concluding "Cogito, ergo sum" ("I 10 think, therefore I am"). He rejected sensory evidence, using radical doubt to 11 establish that only the existence of his own mind is certain. 12 13 ### Question: How do we know anything? 14 15 How to Know (Descartes’ Method): 16 17 - **Method of Radical Doubt:** Descartes decided to reject any idea that could 18 be doubted, including the existence of his body, the physical world, and 19 sensory input, which he noted could be deceptive. 20 21 - **The Cogito ("I think, therefore I am"):** Even if a "demon" is deceiving 22 him, or he is dreaming, he must exist to be deceived or to have those 23 thoughts. The very act of doubting one's existence confirms it. 24 25 - **Rationalism:** Knowledge is not gained through senses but by clear and 26 distinct perceptions of the mind (reason). 27 28 - **God as Guarantee:** Descartes argued that because he has an idea of a 29 perfect God, that perfect being must exist and would not allow him to be 30 fundamentally deceived about reality. 31 32 ## Propositions 33 34 ``` 35 ____________ ___________ 36 / \ / \ 37 / X \ 38 / / \ \ 39 / / \ \ 40 / / \ \ 41 / / KNOW- \ \ 42 \ TRUTHS \ LEDGE / BELIEFS / 43 \ \ / / 44 \ \ / / 45 \ \ / / 46 \ X / 47 \____________/ \____________/ 48 ``` 49 50 - Left circle: Truths (all true propositions). 51 52 - Right circle: Beliefs (all propositions someone believes). 53 54 - Overlap: Knowledge (propositions that are both true and believed).