Karl Popper

He was a Austrian philosopher, sociologist and science theorist born in 1902, he is considered to be a critic rationalist, he meant that reason gets to a confidence vote but to do this we need to verify the content empirically. For him the Scientific Knowledge is true knowledge but could be wrong, it is not certain.




He expose his vision of the science of philosophy in his work, Logic of Scientific Discovery, he takes the problem of limits between the science and metaphysics, and proposes the search of a Demarcation Problem, to distinguish the scientific propositions of those that aren't. This statement does not decides of the truth or falsity of a proposition, but if can be studied in science, or in metaphysics.














Critic Method: the scientific knowledge is always hypothetical, its mainly localize the mistakes to get the truth, science shouldn't be based on faith, but in reason.




Principle of Falsifiability: in order to a theory to be called as a "scientific", it needs to be fasifiable, the promoter has to prove it with reality to get to the final conclusion, validate it o refute it.




Scientific Theories, are not definitive, is always latent the possibility to find new facts or new discovers, to make a new conclusion and postulate other theory.

Ludwig Wittgenstein

He was an Austrian philosopher and linguist born in 1889, he was the disciple of Bertrand Russell in the Trinity College of Cambridge, later on he was teacher.



During his life he passed trough two different stages of thinking, the first period is the one that goes around his first important work, published in 1923, the Tractatus logico-philosophicus, after he published this work, he left the philosophy believing that he had resolved all the problems related to it, years later, after some stumbles he returned to teach and philosophize, but with a very different thinking and spirit that in his first work, in 1953 he published the Philosophical Investigations (Philosophische Untersuchungen).

His philosophy is divides in those two stages: Logic Philosophy and Language Games.



1st Stage


The thoughts are logic representation of facts, he said that language reflects thoughts, so the language shows us the world, a proposition that can't be proved, shouldn't be said.
For example, you can't say that the world is going to an end in year 2012, because nothing is sure about it.











2nd Stage

As i said before, in the second stage of his works, in this 2nd stage he rejected the previous one, he said that one word can have different interpretations depending its context, he conclude that languages evolve, he called them language games, he thought that what really matter is the use you gave to words not the relation. To say a proposition you first need to know to which language belong.

Plato & other great minds...

He was a rationalist philosopher. He believed in the Theory of Froms. A book that stated that the material world as it seems, is not the real world, but only an image or copy of the real world. He thought that all Good in this world is what gives a sense of being to other Forms in the world. He was the one who came up with the “Allegory Cave” where we briefly explains that men always think they are right, until they’re proven otherwise.

Aristotle:

His epistemology lasted for almost a thousand years. Aristotle was a rationalist, but his main focus was the empiricism. Rejected the Theory of Forms, and believed in the form of the objects. The existence of an essence underlying within the objects. He stated that the true knowledge comes from active reason when perceiving the forms.

William of Ockham:

He was the first thinker in opposing the tendencies of the Middle Ages. He stated that reason obtains knowledge through experience and it can be of two types: complex and uncomplex. Uncomplex is divided in: intuitive, experimental and abstractive. He said “The truths of faith are not self-evident, nor are demonstrable, nor even probable.”

Rene Descartes:

He came up with the mind- body problem. In order to reach absolute certainties you have to start from an absolute doubt. He created his own system known as methodic doubt or Cartesian doubt. He stated that there are two types of substances: reason and matter. “I think, therefore I am” proves the existence of the first one, and he proves the existence of the second one by the existence of God. “If God exists, all my clear and distinct ideas will be true”

Baruch Spinoza:

His doctrine is known as pantheism. He thought that there is just one substance: God, and that he has two attributes thought and extension. He said that all thing in this world are modifications of God. He stated that there are no truth nor false ideas, but adequate or inadequate. There are three levels of knowledge:

Opinion – Imagination: it’s empiric and leads to confusion.

Rational: adequate ideas common to all humankind.

Intuitive: holistic knowledge of God.

G.W. Leibniz:

He said that extension is an illusion and is made of simple and non material beings, called monads; and that physical reality can’t be based in something extensive. He thought that God is the Infinite monad, who created an infinite number of finite monads. Men are perfect Monads (souls) imprisoned in imperfect Monads (bodies). Monads of reason perceive with more clarity than the others, that’s where knowledge is born.

Immanuel Kant

He was a german philosopher born in 1724... It is the first and most important representative of German idealism and is considered one of the most influential thinkers of modern Europe, in the last period of enlightenment and universal philosophy.








He was the promoter of the Criticism, he said that knowledge has limits : human faculties.


His ideas were a combination of Rationalism and Empiricism, he said that both were right in something but also wrong in other matters.


 He reaffirm that knowledge starts in senses, but the reason is the one that orders that information you got trough senses.

One argument he had was that knowledge we obtain requires the combination of reason and experience.

We use the Categories that are rational operations to order the information captured through senses just like space and time.

He thought in 2 concepts to differentiate existing things...

Phenomena o Phenomenon... things that exists, and we CAN perceive, for example you have a apple in front of you, you can see it and then eat it, therefore, you know that that apple does exist.

Nóumena o Noumeno... things that exist, and we CAN NOT perceive, for example you are said that ghosts exist, but you can't see it or touch it.

David Hume

He was a Scottish philosopher and writer, born in 1776, his main ideas are this...




     

• Knowledge emerges from perceptions, whether they are impressions or ideas.

• Sensorial impressions give place to ideas.

              

       

• Concepts such as mind or God fall apart.

He also said that, the logical principles, such as Cause and Effect are just product of imagination, man can't know the nature of the world, this is known as Skepticism.

He was empiricist, this means that the only way of get knowledge is through senses.

Tomb of David Hume in Edinburgh

                         This is because there can be relations of ideas, that those does not tell us nothing about the world, or matter of facts that are uncertain.

Epistemology: Our need to know about knowledge!

EPISTEMOLOGY: Our need to know about knowledge!

Definition

Epistemology is defined as the philosophical branch that studies human knowledge.

Its purpose is to investigate its elements, nature, methods, and limits. It also attempts to answer to basic questions such as: What are the necessary and sufficient conditions for knowledge? What is the difference between true knowledge and false knowledge?

Divisions

Epistemology is divided into several streams, which we will analyze in the following paragraphs:

EMPIRICISM



Stream that states man acquires his knowledge through senses. Knowledge is obvious and evident, and it is perceived or collected through experience. The information that our senses collect is absolutely veridic.

RATIONALISM

Now we get to a much more critic posture than empiricism. It proposes reason as the only valid criteria to determine the validity of our knowledge. This means knowledge is acquired after having analyzed information. Rationalism affirms reason analyzes what senses perceive, but it also considers the possibility that senses can cheat on us.

SKEPTICISM

Posture that states that ensures knowledge is NOT possible. The human being is unable to achieve certain and absolute knowledge of something. This stream presents several levels, from naïve skepticism, which is an absolute incredulous state toward knowledge; to ciritcal skepticism, which is doubt regarding certain objects we will never be able to know.

Still, rationalism presents an inconsistence, because it is contradictory. The posture itself (saying knowledge is impossible) is considered as knowledge!

RELATIVISM

This posture says there doesn't exist an absolute truth, but each individual achieves his own truth. In other words, it limits itself to the possibility of knowledge, since it varies according to multiple factors. It must be fundamented in an argumentative and critic posture, and it is generally subjective.

SOLIPSISM

Otherwise from relativism, solipsism limits to a single knowledge: THE EXISTENCE OF ONE SELF. It states that as much as an individual can know is his inner self. It denies knowledge because of the impossibility of demonstrating a reality external to the inner self.

CONSTRUCTIVISM

It affirms that knowledge is a constant, never-ending labor. This means knowledge is not a whole that can be acquired immediately; we BUILD it progressively. Contemporary science is constructivist, for instance.

Epistemological Questions (&possible answers)

• What is knowledge?

Theoretical and/or practical understanding of matters worth knowing; the sum of what is known

• How do we acquire knowledge?

Through experience.
Through sense perception.
Through a progressive process.

• Is it possible to have knowledge at all?

Yes, of course.
No, because it is NOT possible to demonstrate a reality exernal to the inner self.

• Does reason provide us with knowledge of the world independently of experience?

No, but when we are born we perceive the world with our senses, and this information collected is then called knowledge.

• Does knowledge represent reality as it really is?

This is a question that will never have an answer, because it's possible that each person in the world has a different reality created by himself, that has nothing to do with the real world. Or maybe, reality is inside of us; the real world is only us with what our minds create.

• What are the elements of knowledge?

The process of knowing something includes three elements: The subject that will acquire any knowledge, the object that will be studied by the subject, and the idea.

• How can the concept of false knowledge be defined?

When our senses collect information that is not entirely veridic; for instance, the color or shape of something. Or, for instance, thinking you know the naswer, but you do not.

• What makes justified beliefs justified?

The possesion of evidence, which makes us believe something.

• How we are to understand the concept of justification?
• Is justification internal or external to one's own mind?

Plato & Aristotle: The greatest minds of ancient philosophy

PLATONISM

¨The name of Plato’s philosophical branch is Platonism, following the name of its creator.

¨The central concept of Platonism is the “Theory of Forms”

¤A belief that states that the material world as it seems, is not the real world, but only an image or copy of the real world.

¨This belief was taught to Plato by his teacher, Socrates.

¨“He who sees with his eyes is blind” (Socrates)

Allegory of the cave

Plato divided reality into:

 

The Sensible World		The World of the Forms
images of things	things	mathematical forms	higher forms

¨“Form of the Good”

¤States that all Good in this world is what gives a sense of being to other Forms in the world; it must be beyond all being and knowledge. He even compares it with the sun.

ARISTOTELIANISM

Whereas Plato suggested that man was born with knowledge, Aristotle argued that knowledge comes from experience; a stream called EMPIRICISM.

¨Aristotle argued that there were universal principles but that they are derived from experience. He didn’t accept that there was a world of Forms beyond space and time. Aristotle argued that there were Forms and Absolutes, but they resided in the thing itself.

• He considered the soul as a living force

• SUBSTANCE: divided into matter and form. Unlike Plato, Aristotle said forms were inseparable from matter.

Even when this figure is not a real horse, you would identify the horseness of it, right? Because the form is inseparable from the matter.

• Aristotle also divided reality into 5 levels:

1- Inorganic Level: (rocks, seeds, water, and all the non-living elements of nature)
2- Plant Level
3- Animal Level
4- Human Level
5- Heavenly Level (the moon, the stars, and planets are also living things)