Knowledge and Evidence

“What grounds or beliefs in reality are the reasons we have for them”

- Plato

“…are any things that exist independently of us that cannot be the immediate objects of our sensations.“

- George Berkley

Metaphysics- Reason (evidence) for reality?

• Tries to explain truth and knowledge?– Why we believe the things we do?

• Two big camps:– Our senses tell our brains what to do (empiricists)

• Objects are how we sense them– Reason is used to understand an objective reality

(rationalists)• Objects and properties

• How do non physical ideas fit into this world?• Love, Freewill, Passion

TruthInformation that we believe to be true and for which we have experiences for justification and evidence.

• Rationalist: Truth through reason (computer, objective) Truth is dependent on correct definitions (categories)• Empiricist: Truth through senses (virtual reality, subjective)

Truth is dependent on correct interpretation of experience

Truth, external world (infer)– R: mind-independent objects and a physical

nature?– E: Immediate experience and inference,

through 5 senses• What makes truth? Answer two questions

– Is there a solid evidence that allows us to infer the conclusion?

– What is the best process to understanding that evidence?

• Problems– Empiricists: What are the right senses?

(Descartes)– Rationalists: What is the standard of evidence

needed to make TRUTH (belief becomes knowledge)?

Rationalist – Independent TruthFor animals do not see in order that they may have sight, but they have sight that they may see - Aristotle

Truth= Is this a table? What are the qualities?

Empiricists- Dependent truth“If a tree falls in a forest and no one is around to hear it, does it make a sound?” ― George Berkeley

Truth=Am I sensing a table or a chair?

Biases truth – “our truth”

• Social Peer Pressure– Politics

• Other Beliefs– Our family tree of thought

• Misevaluation and Assumptions– Mistakes or predications with no basis

• Lack of cognitive skills– Don’t have the tools – Critical Thinking

WHO CARE ABOUT TRUTH!Maybe we are better off if we try to understand the relationship

between BELIEF and KNOWLEDE

Belief and knowledge – the truth process?

Knowledge- Historical thoughts• Truth is knowledge (Plato/Socrates)– Gods create perfect objects– archetypes. Imperfection our in the

human world.– Physical objects have properties– Knowing all the properties is knowledge?

• Impression is knowledge (Locke/Hume)– Experiences make impressions in our mind. – Knowledge is just a bundle of impressions– Matters of fact are contingent on experiences

• Social norms is knowledge (Rousseau)– “Let the child be a child”, we learn by participation (society)– Real wisdom is not the knowledge of everything, but the

knowledge of which things in life are necessary, which are less necessary, and which are completely unnecessary to know.

Rationalists knowledge

• Plato states, “we can only know things that are absolutely true.”– 100% true all the time…requires certainty– Very hard standard to meet– Think of the problems Descartes had just trying

to prove the simple fact that he, himself, existed.

– Now extend out to other things

Problem with rationalists knowledge• How much then?

– 51%– Beyond a REASONABLE DOUBT?– Best explanation

• What standard do you use to claim you KNOW something?

Empiricists Knowledge

• We know things by experiencing them– You need to test the claim yourself

• The process of knowing that is important• Reality cannot exists without the a sensation

connected with it. • No truth around us, we make our truth

Problems with empiricism

• What of Memory• How do we retain Beliefs to form knowledge?• How do we know of senses are correct

– Descartes doubts (sight, feeling)• How can we ever have community discussion

or laws or commonality?• How do we process senses? No truth?

Immanuel KantReality & Knowledge--

objectiveWe indeed, rightly considering objects of sense(s) as mere appearances..[appearances] are based on upon a thing in itself, though we know not this thing in itself, but only know its appearance, namely, the way in which our senses are effected by this unknown thing.

Immanuel Kant- Beliefs subjective

Knowledge comes from understanding physical world with good reason. However– Noumenal: Things lying beyond senses [objective world], "things-in-themselves” never 100% know truth of these– slighted by perception.. truth is impossiblePhenomenal: Beliefs confirmed or denied by perception (senses), organized and structured by the mind (reason). This becomes knowledge.

Immanuel Kant– 5 steps• The human mind does not receive and imprint ideas

of objects onto a blank slate (impressions). Experience does not make knowledge.

• There is no knowledge without the reasoning skills first. (Computer processor)

• World exits independent from the mind. The mind must sort out knowable things and beliefs. (Proof)

• Every effect has a cause. Objective and independent from experience.

• Knowing comes from knowing cause and effect relationships. This is reality and truth

Tree of knowledge• Roots are our strongest held

knowledge– Strongest and hold up the

beliefs• Highest points limbs are our

least held beliefs– Weak, but support our

knowledge • Water and sun are the

evidence that help the beliefs and knowledge grow

Volmar’s TreeThe Role of Reason– “the sap”• Filters evidence- good or bad• Connects our beliefs to reality– valid or invalid• Importance of skepticism- thoughts, ideas,

memories, emotions are fair game for investigation • Through perception (evidence) reason beliefs

becomes knowledge.– good sap = good roots

Evidence Characteristics – Logic, organized beliefs• Proves or disproves a viewpoint or statement. • Premises lead to the conclusion

All apples are RedThis is an apple

----------------------------Therefore, it is red

Evidence, or premises, can be true or false

Evidence Characteristics – Know influences• Big event– sticks with us more• Suggestive or leading language

– How fast were you going when you….• Collided with that car (guilt)• Slid together with that car (even)• That car collided with you (innocence)

• False memory (beliefs)– Recalling an event that never happened– Wrong about the event

Evidence Characteristics – Source credibility (Expert in the field)• Appeal to inappropriate authority

– My uncle says I have a fever– My barber says my radiator needs fixing

• Factors of credibility– Education…training– Experience…work in the field– Reputation…other in the field view – Accomplishments…awards in the field

Evidence Characteristics – Evaluation knowledge base• Confirmation Bias

– Look for only evidence that supports your view• Looking for your side• Blinded by the truth

• Contradiction in evidence– Not only why your claim is good– BUT why the other claims are bad

• Human Egotism – We like to be right!– Physically- releases endorphins– Mentally- emotional comfort