H2 Pioneering philosophers of mind: Descartes, Locke, and Leibniz
René Descartes (1596-1650) : identity crisis, dismissed math (never been applied to solution of
important problems), literature (makes us imagine impossible things), philosophy (never produced
anything which isn’t in dispute & consequently doubtful & uncertain) → became philosopher:
mechanistic expl for traditional fucnt psyche.
Traditional view: sensed, reacted, moved because had sensitive souls.
Mind & body interact but diff entities, requiring own analysis & expl.
John Locke & Gottfried Wilhelm Leibniz: promoted crucial ideas in mental philosophy that combined
& coalesced as foundations of scientific psy.
Descartes: 1618 end self-imposed isolation & see if ‘real-world’ could offer more satisfying knowledge
than academic → soldier
Any point in space could be defined by its numerical distances from arbitrarily defined lines & shape
of moving point’s course could be defined by sequence of such numbers. (integrating geometry w/
algebra) = analytic geometry
New method (deeming) of obtaining true knowledge. Never accept anything as true unless presented
itself so clearly & distinctly in mind → no reason to doubt.
Geometry-like mode of reasoning: small number of self-evident & true axioms. Links together in small
but logically correct steps to arrive at complex but true conclusion of theorems. Simple natures =
elementary & fundamental properties of physical phenomena → couldn’t be analyzed/doubted:
extension (occupied space by body) & motion (movement of body). All physical phenomena expl by
these. Sensory impressions resulted from motions & interactions of extremely small material
bodies/particles.
Galileo Galilei: physical reality depended on interactions material particles having 3 primary
qualities: shape, quantity, motion.
Result is creation of secondary qualities: sensory exp.
Descartes: extended particles in motion (Democritus), but denying move in void or vacuum. Entire
universe completely filled w/ 3 diff material particles in diff kinds of motion. Space gets filled (like a
fish swimming). Fire, air, earth (light, filling space between objects, solid material).
Vibrations from particles are transmitted through air particles (vision) → set of mechanistic
responses. Operating according to physical laws.
Anatomical studies. Particularly syst of nerves. Animal spirits (cerebrospinal fluid). Thought nerves
were hallow.
Vibrations stimulate sense receptors, pulling a fiber in the long nerve → open a valve in brain. Animal
spirits contained in brain cavity & enter long nerve to travel back resulting in reaction =
unconditioned reflex.
Stimulus arriving from 1 nerve might be transmitted to valve opening the pore of a diff one →
conditioned reflexes → response
Beh responses infl by internal emotional factors → localized commotions (currents/eddies) cause.
Arise from animal spirits.
Body’s response combination of external stimulation acting & internal ‘emotional’ preparedness of
animal spirits to respond.
‘Discourse on Method’ (autobiographical): everything uncertain
Diff between wakefulness & sleep: in wakefulness ventricle max filled & expanded w/ animal spirits.
Stretching brain tissue & exposed nerve fibers into tautness & max sensitivity to external stimulation.
In sleep empty: incapable of transmitting signals. Dreams: transmitting signals.
Nonhuman animals completely understood in mechanistic terms (automata). More complicated than
human.
Machines + rational soul → interact
Couldn’t doubt that he was doubting (distinct from body) : “I think, therefore I am”.
,Soul never appeared directly/completely in consc. Innate ideas of the mind (perfection, unity,
infinity).
Senses trusted because mind perceived it.
Dualist: distinction body & mind
Interactions: ratio guides survival. Other times conflict. Interactive dualism.
Princes Elizabeth of Bohemia (friend): questioned interaction mind & body.
Descartes: body w/out soul = automaton: only mechanistic control of external stimuli & internal
hydraulic condition. Soul innate ideas → lack sensory impressions & ideas.
Location where impressions eyes unite → in brain → pineal gland (undivided).
Image on retinas → excite nerves to project & upright single image onto pineal gland.
Also free will: enhancing, inhibiting, redirecting, modifying fluids (animal spirits). Infl reflexive beh
responses w/ reason.
Consc exp commotions = passions. Infl emotion’s effect (moving gland)
Consc, subjectivity & volition related to physical funct brain/nervous syst.
John Locke (1632-1704): ‘An Essay Concerning Human Understanding’. Not appreciate criticism →
Gottfried Leibniz expanded essay (New Essays on Human Understanding)→ fictional representative
of Locke engages in Platonic-style dialogue w/ mouthpiece for Leibniz.
Both infl by Descartes (physics & physiology).
Locke active consc soul creating exp of world. More sides to viewpoints.
Follower & friend of Robert Boyle (1627-1691): Boyle’s law (volume of gas varies w/ pressure).
Practical elements of science & medical + Descartes’s work.
Due Sir Anthony Asley Cooper (1612-1283) involved in politics & medical advisement → liberal.
Important Britain scientific organization. Fled for political reasons to Holland.
Inexp mind = tabula rasa (blank slate). Mind receptacle for info form outside world. Abstractions
required in minds that already have exp.
Exp mind: sensations external world & reflections of mind’s operations → memories
Simple ideas = earliest sensations & reflections
Exp: simple ideas combined by mind = complex ideas
All simple components must be previously exp.
William Molyneux (1656-1696): blind man identifies w/ touch → if could see: not tell things apart.
Newly exp.
Locke: nature of knowledge: immediate & irresistible perceptions = intuitive knowledge (differences).
Demonstrative knowledge = geometric or logical reasoning. Conclusion not obvious, but true.
Sensitive knowledge = sensory exp.
Association of ideas: lining together/combining ideas.
Contiguity = simultaneously/rapid succession: law of association by contiguity
Similarity = ≥2 exp ideas: law of association by similarity
Objects primary qualities: solidity, extension, figure & mobility
Secondary qualities less certainty: expl in terms of basic primary qualities.
How to resolve moral, religious, political disagreements.
Self-interest leads to social contact.
(Thomas Hobbes 1588-1679). Survival required absolute obedience.
Locke: learn from exp, profit from combined exp of groups.
Gottfried Wilhelm Leibniz (1646-1716): mathematics: mechanical (precursor modern computers),
binary arithmetic, infinitesimal calculus. Calculus dealt w/ constant & continuous change variables.
Mathematical equations did mirror & predict concrete reality.
Benedict Spinoza (1632-1677): pantheism (god = entire universe) & Antonie van Leeuwenhoek
(1632-1723): modern microscope.
, Sophie the Countess Palatine & daughter Sophie Charlotte audience for Leibniz’s philosophizing.
Believer in importance of info exchange. Scientific interest in non-western psychologies & modern
cultural psy. Science & technology ↔ civility & harmonious living
Full dimensions of philosophy of mind for the emerge of scientific psy.
Teeming population of micro-organisms. One can’t arrive at tiny piece of extended matter & say it’s a
ultimate being. Changes directed or ‘purposive’ causes in nature.
Monads = ultimate components energetic & purpose-laden w/ awareness → hierarchy of 4 general
classes:
1. Bare monads: faintest capacity of awareness. Clustered together from basis of physical
bodies of material objects.
2. Sentient monads: consc sensation & perception of material objects, memory & exp. Joined
physical body → dominant monad/soul
3. Rational monads: occupy assemblages of sentient monads to become mind. Beyond simple
perception to incl apperception = further interpretation, studied, rationally analyzed in terms
of underlying principles of laws.
4. Supreme monads = God. Purposes, perceptions, apperceptions & higher degrees of
awareness controlled & contained everything else in universe. Understood & controlled
everything
Each monad own innate purposes & destiny.
Leibniz: visionary theorizing, wide-ranging & highly imaginative intellect.
Locke: more practically minded. Understand empirical world in mechanistic way.
Essay critique on Locke from Leibniz: more nativist doctrine. Soul inherently contains sources of
various notions & doctrines, which external objects merely rouse up on suitable occasions. Innate
mental capacities. Mind is veined block of marble whose internal fault lines predispose it to be
sculptured in some shapes more easily than others. Innate ideas & predispositions = necessary
truths.
Animals lack logical reasoning because lack of innate necessary truths required.
Mind is constantly active.
Minute perceptions in bare monads. Never individually enter consc. Infinity of perceptions at every
moment, but unaware. Can rise level of full perception. Role in motivation. Determines beh.
Locke: view infl in English-speaking areas. Founder of psy tradition: British associationism.
Association principles to syst analysis of visual (depth) perception. Learned associations. Skeptical
analysis of concept of causality.
Early attempt neurophysiology: ideas subjective results of minute vibrations in specific locations of
brain that become interconnected or associated by nerve networks.
Diff personal character results from association principles. Nature-nurture debate.
Behaviorism → Lockean ideas together
Leibnizian: focus on properties & activities of mind itself. Unconsc infl on beh: hypnotists &
psychoanalysis.
H3 Physiologists of mind: brain scientists form Gall to Penfield
Franz Josef Gall (1758-1828): brain as complex organ responsible for higher mental funct. Substance
of brain structures rather than spaces & fluids: Thomas Willis (1621-1675). Gray & white matter
(narrow canals distribute ‘spirits’ generated in gray matter)
Gall: strokes & injuries brain affect body.
2 halves are interconnected by commissures (nerve tissue/white matter) & white fibers cross over
from each side of brain to connect w/ opposite sides of spinal cord. Nerve cells = neurons
