El empirismo de John Locke

Imagina a John Locke, en la Inglaterra del siglo XVII, un hombre genial, pragmático y muy curioso (ya les dije que era médico y famoso como cirujano), paseando por los jardines frondosos de Oxford o acaso recluido en su estudio rodeado de libros. Harto de las especulaciones abstractas de filósofos como Descartes, que construyen castillos en el aire con ideas innatas y razón pura, Locke decide emprender su propia búsqueda: ¿de dónde viene realmente el conocimiento humano? 

No en sueños demoníacos ni en intuiciones divinas, sino en la tierra firme de la experiencia cotidiana. 

Comienza cuestionando las "ideas innatas" defendidas por Descartes. ¿Será cierto que un niño nace con las verdades grabadas en el alma... ¿Dios o el bien y el mal? Locke concluye que esta no puede ser toda la verdad. No es que la razón cartesiana no tenga sentido. El asunto es que Descartes no le da importancia a la experiencia. Para él, los sentidos son engañosos. 

NO, LA EXPERIENCIA ES FUNDAMENTAL. 

Es entonces que Locke propone en su famoso libro An Essay On Human Understanding que la mente es una tabula rasa (una pizarra en blanco), vacía al nacer, esperando que el mundo la escriba. Todo conocimiento surge de los sentidos: primero, las sensaciones simples: como el calor del sol en la piel o el rojo de una manzana, que imprimen "ideas simples" en la mente. Luego, la reflexión interna, como combinar esas ideas en complejas, forjando conceptos de causa, efecto o sustancia.

Pero Locke no es bobo. Sabe que los sentidos pueden engañar, como un bastón torcido en el agua. Aquí entra su realismo representativo: Los humanos no percibimos el mundo directamente, sino a través de "ideas" que lo representan. Vienen a ser como cuadros en una galería mental. 

Estas ideas provienen de cualidades primarias (sólidez, forma y movimiento) existentes en los objetos mismos y cualidades secundarias (subjetivas, como color o sabor u olor, que dependen de nuestra percepción). 

Tomemos como ejemplo una manzana. Aquí tenemos cualidades primarias: solidez de la manzana, forma: redonda. Y cualidades secundarias: el color rojizo, el sabor agridulce de la manzana, su olor, etc.  

Así, el empirismo se revela como un puente confiable entre el yo y la realidad externa: no hay conocimiento sin experiencia, y la razón solo organiza lo que los sentidos entregan. De esta odisea humilde y observadora, Locke emerge con una filosofía anclada en lo tangible, un antídoto al escepticismo cartesiano, proclamando que el entendimiento humano es un explorador, no un oráculo innato.

La duda que nos lleva a la certeza (de acuerdo a Descartes)

 

Imagina a René Descartes, solo en su habitación iluminada por una vela parpadeante, en una fría noche de invierno en Holanda. Decidido a construir el conocimiento sobre cimientos inquebrantables, adopta el racionalismo puro: solo aceptará como verdadero aquello que resista cualquier duda posible.Comienza su odisea intelectual dudando de todo. ¿Los sentidos? Engañosos, como ilusiones ópticas o sueños vívidos donde cree estar despierto. 

¿Y la realidad externa?

Podría ser una matriz creada por un demonio malvado, manipulando sus percepciones. Incluso las matemáticas simples, como 2+3=5, podrían ser falsas si ese demonio lo engaña en su mente.Pero en medio de esta tormenta de escepticismo, surge un rayo de luz irrefutable. Mientras duda, se da cuenta de que está pensando: dudando, reflexionando, cuestionando. Ese acto de pensar no puede ser ilusorio, porque para ser engañado, debe existir algo que sea engañado. Así, llega a la certeza absoluta: "Pienso, luego existo" (Cogito ergo sum). Es el punto de partida indudable, una verdad clara y distinta que no depende de nada externo, solo de la razón pura. De ahí, reconstruirá su filosofía, como un náufrago que encuentra una roca sólida en el mar de la incertidumbre. 

En la Primera Meditación, invoca el escepticismo radical: duda de los sentidos, que a menudo engañan con ilusiones o sueños indistinguibles de la vigilia.  Pero va más allá, conjurando la figura aterradora de un "genio maligno" (le malin genie) o demonio omnipotente, un ser astuto que podría estar manipulando su mente, haciendo que crea en un mundo externo falso, e incluso en verdades matemáticas aparentes como 2+2=4.

Bajo esta sombra demoníaca, todo se derrumba en la incertidumbre absoluta: ¿y si este engañador supremo lo induce a error en cada pensamiento? Sin embargo, en la Segunda Meditación, emerge un destello invencible. Mientras duda de todo, se percata de que el acto mismo de dudar implica pensar. 

Para que el demonio lo engañe, debe existir un "yo" que sea engañado. Así, irrumpe la certeza luminosa: "Pienso, luego existo" (Cogito ergo sum). Esta verdad no depende de los sentidos ni del mundo externo, ni siquiera del demonio; es una intuición clara y distinta de la razón pura, el archimedeo punto fijo desde el cual Descartes reconstruye su metafísica, demostrando que el demonio, por poderoso que sea, no puede anular la existencia del pensador.

Homework #5 (Epistemology, 2025)

IDEALISM/RATIONALISM

1. ¿What are the general requirements for knowledge?

2. ¿Can you have a true belief without having knowledge? Provide an example. 

3. Briefly answer: ¿Is suspension of belief similar to doubt? ¿Is it preferable to suspend than falsely believe? ¿How can you tell? 

4. From the textbook. 6.2 on Rationalism p. 289.  

5.  Is number five an objective entity for Plato? Explain. 

6. Briefly explain Plato's FORMS?

8. Briefly comment on Descartes' doubt and Descartes' certainty.

From the Textbook, exercise 6.2, page 301. Answer  #1, #2, #4, #5

EMPIRICISM

9. From the textbook, Section 6.3, page 319. Answer questions #1- #4 

(35 words at least per answer)

Homework #4 Epistemology

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SCIENTIFIC REVOLUTIONS (AND THE DIFFERENCE BETWEEN HYPOTHESIS)

THOMAS KUHN 

He explains a scientific revolution as a radical shift in how a scientific community understands and investigates the world. In his landmark book The Structure of Scientific Revolutions (1962), he contrasts "normal science" with "revolutionary science". IT TAKES FOUR STEPS.  

 1. Normal Science Most of the time, scientists work within a paradigm: a shared framework of theories, methods, and assumptions that defines legitimate problems and acceptable solutions. Normal science is puzzle-solving—scientists refine theories, run experiments, and accumulate knowledge, but always within the accepted paradigm. 

 2. Crisis Over time, anomalies—observations or problems the paradigm cannot explain—accumulate. If these anomalies persist and become too severe, they trigger a crisis of confidence in the existing framework. 

 3. Scientific Revolution A new paradigm emerges that explains both the old data and the anomalies more effectively. This change is not gradual but discontinuous and radical: the scientific community abandons the old worldview in favor of a new one. Examples: the Copernican revolution (heliocentric astronomy), Newtonian mechanics replacing Aristotelian physics, Einstein’s relativity overturning Newtonian space and time. 

4 . Incommensurability According to Kuhn, old and new paradigms are often incommensurable: they use different concepts, standards, and languages, making direct comparison difficult. Thus, a revolution is not just progress but a redefinition of reality itself within the scientific community.

 IMRE LAKATOS (1922–1974) 

 Developed the idea of “research programmes” as a refinement of Kuhn’s paradigms. Each programme has a “hard core” (fundamental assumptions that are not easily abandoned) and a “protective belt” (auxiliary hypotheses that can be adjusted to handle anomalies). Unlike Kuhn’s abrupt revolutions, Lakatos sees science as competing research programmes where one is judged progressive (predicting novel facts) or degenerative (patching itself defensively). Example: Newtonian mechanics gradually giving way to Einstein’s relativity can be seen as the rise of a progressive programme. 

 PAUL FEYERABEND (1924–1994) 

 Famous for Against Method (1975). He rejected rigid paradigms altogether, advocating epistemological anarchism: “anything goes.” For him, science advances not by fixed paradigms or methods, but by pluralism, creativity, and often by breaking rules. He agreed with Kuhn that scientific revolutions involve radical shifts, but stressed the messy, unpredictable, and political side of them. 

 LARRY LAUDAN (1941–2022) 

Proposed “research traditions” (similar to Kuhn’s paradigms and Lakatos’s programmes). He emphasized the problem-solving effectiveness of a tradition as its measure of success. Instead of incommensurable breaks, Laudan envisioned a more continuous, rational debate between traditions. 

 BRUNO LATOUR 

From the 1980s onward, Latour and others in Sociology/anthropology of science describe paradigm shifts not as purely intellectual but as network reconfigurations involving instruments, institutions, and power. For Latour, a “revolution” is a realignment of both ideas and material practices. 

SO, 

Kuhn introduced paradigms and incommensurability. 

Lakatos systematized it into research programmes. 

Feyerabend radicalized it with epistemological anarchism. 

Laudan softened it into rational research traditions. 

Latour reframed it as network transformations. 

Review for Quiz 2025

 Fallacies

1. Read the following argument: “Of course God exists, because the Bible says so, and the Bible is true because it is the word of God.” a) Identify the fallacy. b) Explain why the reasoning is circular. c) Rewrite the argument in a way that avoids begging the question. 

PETITIO

 2. A student claims in debate: “We shouldn’t take Miguel’s argument about climate change seriously, because he doesn’t even recycle.” a) Identify the fallacy. b) Suggest a more appropriate way to respond to Miguel’s position. 

AD HOM

3. Consider the following statement: “Either you support government surveillance programs, or you don’t care about national security.” a) Identify the fallacy. b) Explain why this argument oversimplifies the situation. c) Propose at least two alternative positions that show the issue is more complex. 

Exercise: A friend says: “No one has ever proved that extraterrestrial life doesn’t exist, so aliens must be real.” a) Identify the fallacy. b) Explain why lack of evidence is not proof. c) Give an example from science where something remained unproven until later, but that didn’t justify believing it existed. 

APPEAL IGNORANCE

5. “Italians are all terrible drivers!” a) Identify the fallacy. b) Suggest what kind of evidence or sample would be necessary to make a stronger generalization. 

HASTY G

Necessary and sufficient conditions

1. “Being divisible by 2 is required for a number to be divisible by 6.” 

 a) Is divisibility by 2 a necessary, sufficient, or neither condition for divisibility by 6? b) Justify carefully: show why divisibility by 2 is required, but also why it doesn’t by itself guarantee divisibility by 6. c) Identify another condition that, combined with divisibility by 2, would be sufficient for divisibility by 6. 

 NEC.

 2.  “Believing in democracy is what makes someone a good citizen.” 

a) Is belief in democracy a necessary, sufficient, or neither condition for good citizenship? b) Analyze why it fails as both necessary (a good citizen may act responsibly without professing democratic belief) and sufficient (belief alone doesn’t guarantee good citizenship without corresponding action). c) Suggest one necessary condition for good citizenship, and one sufficient condition (even if it’s somewhat idealized).

NEITHER

 3.  “Having exactly four sides of equal length and four right angles ensures that a figure is a square.” 

 a) Is this description a necessary, sufficient, or neither condition for being a square? b) Explain why this description is sufficient but not always necessary if we change the context (e.g., in non-Euclidean geometry, or with definitions that require additional properties like being a polygon in a plane). c) Propose another condition that would also be sufficient for a shape to count as a square. 

SUFFICIENT

Mind experiments

For this exercise, I'm providing (in italics, below) a mind experiment based on this example about the American Civil War at the Battle of Gettysburg (1861–1865). I want you to construct a mind experiment to explore whether it was causally possible for events to have turned out differently. 

“In July 1863, the Union Army defeated the Confederates at Gettysburg.” 

1. Now, I introduce a counterfactual. It begins with "Suppose that". It alters one relevant cause, factor, or condition. 

Example: Suppose General Lee had received accurate intelligence about Union troop movements before the battle. 

a) Now explain the causal pathway. Analyze how this altered factor might plausibly have changed the outcome. 

Here's an example: “With accurate intelligence, General Lee might have avoided Pickett’s Charge, preventing Confederate losses and perhaps prolonging the war.” 

2. Now, defend the causal plausibility you provide with three points (a, b, c,):  

a) Show why this is not mere fantasy but a serious causal possibility: Was it physically possible? Historically coherent? Supported by the context of the situation?  

b) What does this teach us about causation, necessity, and contingency in history? 

c) Does it show that the outcome of the Civil War was inevitable, or contingent on small changes?

Here is your historic situation:

The assassination of President Lincoln, by John Wilkes Booth, while attending the play "Our American Cousin" at Ford's Theatre in Washington, D.C., April 14, 1865.

a) Do what I did above: Introduce your counterfactual. Imagine altering one relevant cause, factor or condition. 

b) Defend the causal plausibility you provide

Causal and Logical possibility

1. Consider: "Unicorns exist". LP

a) Is the statement above logically possible? Explain why.

 

b) Given the laws of biology and physics, is it causally possible? Explain. 

c) Suggest what conditions would need to change in our world for it to become causally possible.

2. Examine this claim: “A round square exists.” LI --> CI

a) Is this statement logically impossible? Explain.

b) Is it causally possible? Explain. 

3. Consider: “It rains tomorrow in New York City.” LP CI

a) Is this logically possible? Justify your anwser.  

b) Given the laws of meteorology, Is it causally possible in our world? 

c) Compare this case with one that is logically possible but not causally possible (e.g., “It rains diamonds in New York tomorrow”).

Homework #3 (causation & fallacies)

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How build a mind experiment

Remember: A thought experiment is a tool philosophers use to test an idea by imagining a scenario, where they test conditions of possibility.  

1. Identify the Concept or Problem.

Start with the philosophical issue you want to test. Example: Is morality relative or universal?

2. Construct a Hypothetical Scenario

Now imagine a situation—often unusual, exaggerated, or impossible—that clarifies the concept.

Example: A traveler visits a culture where lying is considered a virtue (moral relativism).

3. Introduce a Twist or Tension

The power of a thought experiment comes from creating a possible contradiction or conflict that forces us to rethink assumptions.

Example: If lying is moral somewhere else, is morality objective?

4. Ask the Key Question

“If lying is good in their culture, is it still wrong in ours?”

5. Draw Out Implications

If morality can vary, then perhaps it’s not universal.

Criteria of Adequacy of scientific theories (muy importante)

1. Consistency: Lack of internal contradictions.

Examples: 

If demand increases while supply is fixed, prices rise.

In a growing economy, demand usually increases.

Prices in a growing economy will always remain stable.

➡️ Each proposition sounds plausible in isolation. But taken together, the third contradicts the causal relationship between supply, demand, and price in the first.

All species adapt to their environment over time.

The coelacanth species has remained unchanged for millions of years.

The coelacanth has continuously adapted to its environment.

➡️ The inconsistency is subtle: if the species has remained “unchanged,” how can it also have “continuously adapted”?  The tension lies in how “adaptation” and “unchanged” are interpreted.

2. Simplicity: Quality of relying on only a small number of assumptions.

Example: Astronomy (Heliocentrism vs. Geocentrism)

Simple model: The planets, including Earth, orbit the Sun in predictable paths.

Assumptions: Only one main principle — the Sun is at the center.

👉 Compared to the older geocentric model (which required dozens of extra assumptions like epicycles and deferents), heliocentrism is simpler because it explains planetary motion with fewer rules.

3. Scope: The number of diverse phenomena observed.

Example: Darwin’s Theory of Evolution by Natural Selection

Scope: Explains a wide range of biological phenomena — the diversity of species, fossil records, antibiotic resistance, similarities in DNA, and adaptations like camouflage or mimicry.

One principle (natural selection) accounts for phenomena from finch beaks in the Galápagos to bacteria evolving in a lab.

4. Conservatism: Quality of fitting well with existing theories.

Example: Einstein’s Theory of General Relativity

Conservatism: General relativity fits well with the well-established framework of Newtonian physics in everyday conditions.

Where gravitational fields are weak and speeds are much less than light, Einstein’s equations reduce to Newton’s law of gravitation.

Thus, relativity did not discard Newtonian mechanics but absorbed it as a special case, while extending the theory to explain phenomena like the bending of light near the Sun or the precession of Mercury’s orbit.

👉 This is conservatism in action: a new theory doesn’t overthrow everything before it, but integrates past successes while going further.

5. Fruitfulness: The number of new facts predicted of problems solved.

Example: The Structure of DNA (Watson & Crick, 1953)

Fruitfulness: The double-helix model of DNA was not just a description of molecular structure — it opened the door to new predictions and discoveries.

From it followed four important consequences:

1. How genetic information is copied (DNA replication).

2. How mutations occur.

3. How genetic coding translates into proteins.

4. Techniques like DNA sequencing, genetic engineering, and forensic DNA analysis.

👉 A single theoretical insight (the double helix) led to a cascade of new facts, experiments, and applications across biology, medicine, and technology.

homework #2

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Etnocentrismo: eslabón fundamental de la cultura

Ayer en la clase me referí a mi cultura como la mejor. 

Trataba de resaltar un punto que desde hace algunos años ha sido mal interpretado por una escuela de pensamiento que aboga por un multiculturalismo distorsionado. La confusión está en mezclar el respeto y la igualdad para el semejante con la disolución de los lazos culturales.    

Le han dado mala fama al etnocentrismo. 

No debía ser así. 

A través de la historia hemos sido fundamentalmente etnocentristas.Y hay razones más que suficientes para serlo. Vamos por parte: 

Primero la familia. De ahì el círculo de las familias: el clan. Nada más poderoso que eso. 

¿Qué es un pueblo? El conjunto de personas de un lugar, región o país. De ahí venimos TODOS. 

De ahí es que sale la cultura. ¿Por qué? La cultura se origina en una región o ubicación específica. La cultura de cada uno de nosotros es con la cual hemos crecido. Salimos de ahí. 

Pongo como ejemplo tres culturas pertenecientes a tres islas del Caribe: Cuba, República Dominicana y Puerto Rico. 

Las tres culturas parecieran muy similares pues comparten lenguaje, clima y geografía. PARA NADA. 

El dominicano no se siente entre los suyos con cubanos ni con puertorriqueños. ¡Se siente como suyo entre los suyos! 

Sí, puede ser un buen amigo de un puertorriqueño o un cubano –y muy íntimo. Pero en general, la mayoría de sus más cercanos son dominicanos. Lo mismo pasa con el cubano y el puertorriqueño. 

¿Por qué? 

Pertenecen a culturas distintas. Así de simple. Se trata de un proceso automático, dado por cientos de años de crecimiento en tu cultura. Es una incorporación y absorción "inconsciente", al nivel de las emociones, vivencias, costumbres, etc. 

Algo muy fuerte. Casi inexplicable.

El impacto cohesivo de la cultura es milenaria

Resulta que ese etnocentrismo es obvio y terco. 

Les cuento mi experimento antropológico "de bolsillo" en Miami Dade Wolfson Campus. En la cafetería de la escuela, durante el desayuno y el almuerzo, los alumnos llenaban el lugar. No resultaba difícil para alguien con una inquietud antropológica o sociológica observar una segregación cultural espontánea. Anglos con anglos, haitianos con haitianos –no con negros americanos. Cubanos con cubanos, venezolanos con venezolanos, salvadoreños con salvadoreños, nicas con nicas. 

¿Quién se atreve a meter la cuchareta e imaginar que esa asociación espontánea es "incorrecta"? 

Simplemente actúan siguiendo las costumbres de sus antepasados durante siglos. Pretender cambiar eso es tonto y además baldío. 

Etnocentrismo sin absolutismo

El etnocentrista simplemente siente que su cultura es principal y fundamental. 

Eso no implica que no pueda admitir lo mismo para otra cultura. 

No le reprocho a un puertorriqueño en lo absoluto que piense que su cultura es la mejor. ¡Lo aplaudo y apoyo! 

El sentimiento de interculturalidad es fuerte. De ahí salen las primeras ciudades del Homo Sapiens.

En mi juventud tuve una novia puertorriqueña que quise mucho. Cuando estaba con ella, sentía que los pertorriqueños eran lo mejor (y me sentía un poco boricua). 

 Y lo mismo digo de salvadoreños, guatemaltecos, argentinos, peruanos, haitianos...