Test Your Knowledge of Qualia



9 Questions

What are qualia?

What is the Mary thought experiment?

What is the hard problem of consciousness?

What is Daniel Dennett's criticism of qualia?

What is David Chalmers' principle of organizational invariance?

What is the inverted spectrum argument?

What is the causal theory of perception?

What is the dual coding theory?

What is the hard problem of consciousness?


Qualia are instances of subjective, conscious experience that cannot be fully conveyed verbally. They include the perceived sensation of pain, the taste of wine, and the redness of an evening sky. Philosophers and scientists disagree about the existence and importance of qualia. Some argue that qualia do not exist and are incompatible with neuroscience and naturalism, while others claim that they do exist. Qualia are often defined as the "what it is like" character of mental states. Thought experiments, such as the inverted spectrum argument and the knowledge argument, are used to argue for the existence of qualia. Critics of qualia, like Daniel Dennett, argue that the concept is flawed and cannot be practically applied. Dennett uses intuition pumps to show that the definition of qualia breaks down when applied to neurosurgery, clinical psychology, and psychological experimentation. He argues that it is impossible to know whether qualia have been inverted or whether memories of past qualia have been inverted.The Mary thought experiment and the concept of qualia

  • Mary is a thought experiment about a person who knows all the physical facts about the experience of color but has never seen color herself.

  • The thought experiment raises questions about whether knowing all the physical facts about an experience gives someone the ability to know what it feels like.

  • RoboMary is an intelligent robot used to illustrate the thought experiment further. RoboMary can construct a simulation of her own brain and simulate how she would react to seeing a red tomato.

  • This example shows that Mary's knowledge makes her own internal states as transparent as those of a robot or computer.

  • It is suggested that Mary's failure to learn what seeing red feels like might be a failure of language or our ability to describe experiences.

  • Michael Tye believes there are no qualia and that our experience of an object in the world is "transparent".

  • Roger Scruton argues that qualia is an incoherent concept and that Wittgenstein's private language argument effectively disproves it.

  • David Chalmers formulated the hard problem of consciousness and argued for "the principle of organizational invariance" which states that if a system reproduces the functional organization of the brain, it will also reproduce the associated qualia.

  • E. J. Lowe defends a version of the causal theory of perception and denies that indirect realism implies a Cartesian dualism.

  • John Barry Maund argues that qualia can be described on two levels, a fact that he refers to as "dual coding".

  • Gary Drescher compares qualia with "gensyms" in Common Lisp, which are objects that have no properties or components and can only be identified as equal or not equal to other objects.

  • D.K. Lewis proposes a different ability hypothesis that differentiates between two types of knowledge: knowledge "that" (information) and knowledge "how" (abilities).Philosophers' and Neuroscientists' Views on Qualia

  • There are two descriptions of qualia: (1) a "commonsense" one which refers to publicly recognizable objects, and (2) an accurate point-by-point account of the actual state of the field that makes no mention of what any passer-by would or would not make of it.

  • Color is seen as a dispositional property, not an objective one. Colors are "virtual properties"; is as if things possessed them.

  • Sensing is complete in itself, it is not like "kicking a football" where an external object is required – it is more like "kicking a kick".

  • Sensory experience can be entirely free of representational character.

  • Qualia are non-material events that are caused by brain events but not identical with them.

  • Qualia are important for the organism's survival and a product of neuronal oscillation.

  • Qualia are created through the neurobiological mechanism of re-entrant feedback in cortical systems.

  • The neural mechanism or network receives input information structures, completes a designated instructional task (firing of the neuron or network), and outputs a modified information structure to downstream regions.

  • Local cortical networks can receive feedback from their own output information structures.

  • The neurobiological manifestation of qualia is representations of the network's own output structures, by which it represents its own information message.

  • Perception of sensory input is necessary in order to navigate and modify interactions with the environment.

  • Most neuroscientists and even most psychologists dispute the very existence of the “problem” of qualia.Issues and Criticisms of Qualia

  • Pyramidal networks in the frontal regions are associated with increased perceptive capacity, which may be the foundation of consciousness.

  • Qualia are unobservable in others and unquantifiable in us, making it difficult to discuss them accurately.

  • Epiphenomenalism acknowledges the existence of qualia but denies them any causal power, which has been criticized by some philosophers.

  • Identifying qualia with external objects may not be the correct approach to sensation, as it threatens the reliability of knowledge.

  • The issue is epistemological, and access to knowledge is blocked if one allows the existence of qualia as fields in which only virtual constructs are before the mind.

  • Viewing sensations as "raw feels" implies that initially, they have not yet been unified into "things" and "persons."

  • The definition of qualia inevitably brings philosophical and neurophysiological presuppositions.

  • Some materialists want to deny the existence of qualia altogether.

  • There are committed dualists who believe that the mental and the material are two distinct aspects of physical reality, and there are direct realists for whom qualia are unscientific.

  • The question of what qualia can be raises profound issues in the philosophy of mind.

  • There are committed proselytizers for a final truth who reject qualia as forcing knowledge out of reach.


How well do you understand the concept of qualia? Take this quiz to test your knowledge about the philosophical and scientific debates surrounding the "what it is like" character of mental states. From the Mary thought experiment to the hard problem of consciousness, this quiz covers various perspectives on the existence and importance of qualia. See how much you know about this fascinating topic and learn more about the issues and criticisms of qualia along the way.

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