Descartes' Dualism and Arguments Against Materialism Quiz

Descartes' Dualism and Arguments Against Materialism

• Materialism is the idea that mental life comes from physical brain.
• Dualism, found in most religions and philosophies, is the idea that humans possess both material and spiritual parts.
• Descartes was a proponent of dualism and argued that while animals are material, humans have a non-material nature.
• Descartes made two arguments for non-material nature: humans can do things no machine could, and humans do not feel like bodies.
• Descartes knew about robots in the 17th century and argued that human behavior is too complex to be explained by simple stimuli response.
• Descartes' second argument is based on intuition and the method of doubt.
• The method of doubt asks what can be questioned, and Descartes observed that many beliefs could be false.
• Descartes argued that consciousness cannot be doubted, leading to his famous line "I think, therefore I am."
• Descartes believed the soul is entirely distinct from the body and does not depend on a material thing.
• Descartes' arguments against materialism continue to persuade many people today.
• Descartes' ideas have been expanded upon by modern-day philosophers who argue that humans may be simulations or brains in a vat.
• The concern about reality and existence is ancient but is best articulated in the movie The Matrix.

The Brain: The Most Complex Machine in the Known Universe

• The brain is the physical seed of thought and the source of our mental life and consciousness.
• Despite its complexity and importance, the brain looks unappealing and meaty when taken out of the head.
• Neurons are the smallest relevant parts of the brain and the focus of most research in neuroscience.
• Neurons receive signals from other neurons through dendrites, which either excite or inhibit them.
• The cell body sums up the pluses and minuses from dendrites, and when it reaches a threshold, neural firing occurs.
• Neural firing takes place through the axon, which is much longer than the dendrites and is surrounded by a fatty tissue called the myelin sheath.
• Neurons sum up and transmit information, and there are billions upon billions of neurons, each connecting to thousands of other neurons.
• Neurons come in three flavors: sensory, motor, and interneurons.
• Neuron firing is all or nothing, but neurons can code for intensity in different ways, such as the number of neurons that fire.
• The brain is the most complicated machine in the universe because of its incredible internal structure and complexity, which cannot be replicated in any machine.
• The brain consists of two halves, the left and right halves, which interact with each other.
• The study of the biological basis of thought is called neuroscience because it all comes from the neurons.

Neurotransmitters, Drugs, and Computational Neuroscience

• Curare is a drug that blocks motor neurons, leading to paralysis and death in large doses.
• Alcohol inhibits a part of the brain responsible for inhibition, making people more exuberant, but can also lead to passing out and death in large doses.
• Amphetamines and cocaine increase the amount of norepinephrine, responsible for general arousal.
• Prozac and L-Dopa increase the supply of dopamine or serotonin, relevant for Parkinson's and depression.
• Drugs work by influencing neurotransmitters either by directly pumping in more or increasing the supply in different ways.
• Neurons form clusters or networks that do interesting things like recognizing faces or walking upright.
• Computational neuroscience aims to understand how neurons are wired up to do interesting things.
• The brain is highly resistant to damage due to how information and capacitors are distributed across neurons.
• The brain is wired up to work very fast despite the slowness of brain tissue and neurotransmitters.
• Massively parallel systems and complicated neural networks are being developed to mimic the brain's wiring for more efficient computing.
• The brain's wiring cannot be compared to a computer's due to its resilience and speed.
• Higher-level explanations of how people learn language or recognize faces will be given instead of direct explanations in terms of neurons.