Combining Philosophers

All the ideas for Hermarchus, Gregory L. Murphy and G Edelman / G Tononi

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46 ideas

8. Modes of Existence / D. Universals / 5. Universals as Concepts
Prior to language, concepts are universals created by self-mapping of brain activity [Edelman/Tononi]
     Full Idea: Before language is present, concepts depend on the brain's ability to construct 'universals' through higher-order mapping of the activity of the brain's own perceptual and motor maps.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.15)
     A reaction: It should be of great interest to philosophers that one can begin to give a neuro-physiological account of universals. A physical system can be ordered as a database, and universals are the higher branches of a tree-structure of information.
12. Knowledge Sources / B. Perception / 5. Interpretation
Research shows perceptual discrimination is sharper at category boundaries [Murphy]
     Full Idea: Goldstone's research has shown how learning concepts can change perceptual units. For example, perceptual discrimination is heightened along category boundaries.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: [Goldstone 1994, 2000] This is just the sort of research which throws a spanner into the simplistic a priori thinking of many philosophers.
13. Knowledge Criteria / E. Relativism / 4. Cultural relativism
Cultures have a common core of colour naming, based on three axes of colour pairs [Edelman/Tononi]
     Full Idea: We seem to have a set of colour axes (red-green, blue-yellow, and light-dark). Color naming in different cultures tend to have universal categories based on these axes, with a few derived or composite categories (e.g. orange, purple, pink, brown, grey).
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13)
     A reaction: This confirms my view of all supposed relativism: that there are degrees of cultural and individual relativism possible, but it is daft to think this goes all the way down, as nature has 'joints', and our minds are part of nature.
14. Science / C. Induction / 1. Induction
Induction is said to just compare properties of categories, but the type of property also matters [Murphy]
     Full Idea: Most theories of induction claim that it should depend primarily on the similarity of the categories involved, but then the type of property should not matter, yet research shows that it does.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: I take this to be good empirical support for Gilbert Harman's view that induction is really inference to the best explanation. The thought (which strikes me as obviously correct) is that we bring nested domains of knowledge to bear in induction.
15. Nature of Minds / A. Nature of Mind / 5. Unity of Mind
A conscious human being rapidly reunifies its mind after any damage to the brain [Edelman/Tononi]
     Full Idea: It seems that after a massive stroke or surgical resection, a conscious human being is rapidly "resynthesised" or reunified within the limits of a solipsistic universe that, to outside appearances, is warped and restricted.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 3)
     A reaction: Note that there are two types of 'unity of mind'. This comment refers to the unity of seeing oneself as a single person, rather than the smooth unbroken quality of conscious experience. I presume that there is no point in a mind without the first unity.
15. Nature of Minds / A. Nature of Mind / 8. Brain
A conscious state endures for about 100 milliseconds, known as the 'specious present' [Edelman/Tononi]
     Full Idea: The 'specious present' (William James), a rough estimate of the duration of a single conscious state, is of the order of 100 milliseconds, meaning that conscious states can change very rapidly.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12)
     A reaction: A vital feature of our subjective experience of time. I wonder what the figure is for a fly? It suggests that conscious experience really is like a movie film, composed of tiny independent 'frames' of very short duration.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / b. Essence of consciousness
Consciousness is a process (of neural interactions), not a location, thing, property, connectivity, or activity [Edelman/Tononi]
     Full Idea: Consciousness is neither a thing, nor a simple property. ..The conscious 'dynamic core' of the brain is a process, not a thing or a place, and is defined in terms of neural interactions, not in terms of neural locations, connectivity or activity.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12)
     A reaction: This must be of great interest to philosophers. Edelman is adamant that it is not any specific neurons. The nice question is: what would it be like to have your brain slowed down? Presumably we would experience steps in the process. Is he a functionalist?
15. Nature of Minds / B. Features of Minds / 1. Consciousness / c. Parts of consciousness
The three essentials of conscious experience are privateness, unity and informativeness [Edelman/Tononi]
     Full Idea: The fundamental aspects of conscious experience that are common to all its phenomenological manifestations are: privateness, unity, and informativeness.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 3)
     A reaction: Interesting, coming from neuroscientists. The list strikes me as rather passive. It is no use having good radar if you can't make decisions. Privacy and unity are overrated. Who gets 'informed'? Personal identity must be basic.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / d. Purpose of consciousness
Consciousness can create new axioms, but computers can't do that [Edelman/Tononi]
     Full Idea: Conscious human thought can create new axioms, which a computer cannot do.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.17)
     A reaction: A nice challenge for the artificial intelligence community! I don't understand their confidence in making this assertion. Nothing in Gödel's Theorem seems to prevent the reassignment of axioms, and Quine implies that it is an easy and trivial game.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / e. Cause of consciousness
Consciousness arises from high speed interactions between clusters of neurons [Edelman/Tononi]
     Full Idea: Our hypothesis is that the activity of a group of neurons can contribute directly to conscious experience if it is part of a functional cluster, characterized by strong interactions among a set of neuronal groups over a period of hundreds of milliseconds.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12)
     A reaction: This is their 'dynamic core' hypothesis. It doesn't get at the Hard Questions about consciousness, but this is a Nobel prize winner hot on the trail of the location of the action. It gives support to functionalism, because the neurons vary.
15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality
Dreams and imagery show the brain can generate awareness and meaning without input [Edelman/Tononi]
     Full Idea: Dreaming and imagery are striking phenomenological demonstrations that the adult brain can spontaneously and intrinsically produce consciousness and meaning without any direct input from the periphery.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11)
     A reaction: This offers some support for Searle's claim that brain's produce 'intrinsic' (rather than 'derived') intentionality. Of course, one can have a Humean impressions/ideas theory about how the raw material got there. We SEE meaning in our experiences.
15. Nature of Minds / B. Features of Minds / 4. Intentionality / b. Intentionality theories
Physicists see information as a measure of order, but for biologists it is symbolic exchange between animals [Edelman/Tononi]
     Full Idea: Physicists may define information as a measure of order in a far-from-equilibrium state, but it is best seen as a biological concept which emerged in evolution with animals that were capable of mutual symbolic exchange.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.17)
     A reaction: The physicists' definition seems to open the road to the possibility of non-conscious intentionality (Dennett), where the biological view seems to require consciousness of symbolic meanings (Searle). Tree-rings contain potential information?
15. Nature of Minds / B. Features of Minds / 5. Qualia / c. Explaining qualia
The sensation of red is a point in neural space created by dimensions of neuronal activity [Edelman/Tononi]
     Full Idea: The pure sensation of red is a particular neural state identified by a point within the N-dimensional neural space defined by the integrated activity of all the group of neurons that constitute the dynamic core.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13)
     A reaction: This hardly answers the Hard Question (why experience it? why that experience?), but it is interesting to see a neuroscientist fishing for an account of qualia. He says three types of neuron firing generate the dimensions of the 'space'.
16. Persons / B. Nature of the Self / 7. Self and Body / a. Self needs body
The self is founded on bodily awareness centred in the brain stem [Edelman/Tononi]
     Full Idea: Structures in the brain stem map the state of the body and its relation to the environment, on the basis of signals with proprioceptive, kinesthetic, somatosensory and autonomic components. We may call these the dimensions of the proto-self.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13)
     A reaction: It seems to me that there is no free will, but moral responsibility depends on the existence of a Self, and philosophers had better fight for it (are you listening, Hume?). Fortunately neuroscientists seem to endorse it fairly unanimously.
16. Persons / E. Rejecting the Self / 2. Self as Social Construct
A sense of self begins either internally, or externally through language and society [Edelman/Tononi]
     Full Idea: Two extreme views on the development of the self are 'internalist' and 'externalist'. The first starts with a baby's subjective experience, and increasing differentiation as self-consciousness develops. The externalist view requires language and society.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.15)
     A reaction: Edelman rightly warns against this simple dichotomy, but if I have to vote, it is for internalism. I take a sense of self as basic to any mind, even a slug's. What is a mind for, if not to look after the creature? Self makes sensation into mind.
16. Persons / F. Free Will / 5. Against Free Will
Brains can initiate free actions before the person is aware of their own decision [Edelman/Tononi]
     Full Idea: Libet concluded that the cerebral initiation of a spontaneous, freely voluntary act can begin unconsciously, that is, before there is any recallable awareness that a decision to act has already been initiated cerebrally.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 6)
     A reaction: We should accept this result. 'Free will' was always a bogus metaphysical concept (invented, I think, because God had to be above natural laws). A person is the source of responsibility, and is the controller of the brain, but not entirely conscious.
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability
Consciousness is a process, not a thing, as it maintains unity as its composition changes [Edelman/Tononi]
     Full Idea: The conscious 'dynamic core' of the brain can maintain its unity over time even if its composition may be constantly changing, which is the signature of a process as opposed to a thing.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.12)
     A reaction: This is the functionalists' claim that the mind is 'multiply realisable', since different neurons can maintain the same process. 'Process' strikes me as a much better word than 'function'. These theories capture passive mental life better than active.
18. Thought / B. Mechanics of Thought / 3. Modularity of Mind
Brain complexity balances segregation and integration, like a good team of specialists [Edelman/Tononi]
     Full Idea: A theoretical analysis of complexity suggests that neuronal complexity strikes an optimum balance between segregation and integration, which fits the view of the brain as a collection of specialists who talk to each other a lot.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11)
     A reaction: This is a theoretical point, but comes from a leading neuroscientist, and seems to endorse Fodor's modularity proposal. For a philosopher, one of the issues here is how to reconcile the segregation with the Cartesian unity and personal identity of a mind.
18. Thought / B. Mechanics of Thought / 4. Language of Thought
Information-processing views of the brain assume the existence of 'information', and dubious brain codes [Edelman/Tononi]
     Full Idea: So-called information-processing views of the brain have been criticized because they typically assume the existence in the world of previously defined information, and often assume the existence of precise neural codes for which there is no evidence.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.11)
     A reaction: Fodor is the target here. Searle is keen that 'intrinsic intentionality' is required to see something as 'information'. It is hard to see how anything acquires significance as it flows through a mechanical process.
18. Thought / C. Content / 6. Broad Content
Consciousness involves interaction with persons and the world, as well as brain functions [Edelman/Tononi]
     Full Idea: We emphatically do not identify consciousness in its full range as arising solely in the brain, since we believe that higher brain functions require interactions both with the world and with other persons.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Pref)
     A reaction: Would you gradually lose higher brain functions if you lived entirely alone? Intriguingly, this sounds like a neuroscientist asserting the necessity for broad content in order to understand the brain.
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
The main theories of concepts are exemplar, prototype and knowledge [Murphy]
     Full Idea: The three main theories of concepts under consideration are the exemplar, the prototype and the knowledge approaches.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
18. Thought / D. Concepts / 2. Origin of Concepts / a. Origin of concepts
Concepts and generalisations result from brain 'global mapping' by 'reentry' [Edelman/Tononi, by Searle]
     Full Idea: When you get maps all over the brain signalling to each other by reentry you have what Edelman calls 'global mapping', and this allows the system not only to have perceptual categories and generalisation, but also to coordinate perception and action.
     From: report of G Edelman / G Tononi (Consciousness: matter becomes imagination [2000]) by John Searle - The Mystery of Consciousness Ch.3
     A reaction: This is the nearest we have got to a proper scientific account of thought (as opposed to untested speculation about Turing machines). Something like this account must be right. A concept is a sustained process, not a static item.
Concepts arise when the brain maps its own activities [Edelman/Tononi]
     Full Idea: We propose that concepts arise from the mapping by the brain itself of the activity of the brain's own areas and regions.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch. 9)
     A reaction: Yes. One should add that the brain appears to be physically constructed with the logic of a filing system, which would mean that our concepts were labels for files within the system. Nature generates some of the files, and thinking creates the others.
18. Thought / D. Concepts / 4. Structure of Concepts / c. Classical concepts
The classical definitional approach cannot distinguish typical and atypical category members [Murphy]
     Full Idea: The early psychological approaches to concepts took a definitional approach. ...but this view does not have any way of distinguishing typical and atypical category members (...as when a trout is a typical fish and an eel an atypical one).
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: [pp. 12 and 22] Eleanor Rosch in the 1970s is said to have largely killed off the classical view.
The theoretical and practical definitions for the classical view are very hard to find [Murphy]
     Full Idea: It has been extremely difficult to find definitions for most natural categories, and even harder to find definitions that are plausible psychological representations that people of all ages would be likely to use.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
Classical concepts follow classical logic, but concepts in real life don't work that way [Murphy]
     Full Idea: The classical view of concepts has been tied to traditional logic. 'Fido is a dog and a pet' is true if it has the necessary and sufficient conditions for both, ...but there is empirical evidence that people do not follow that rule.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: Examples given are classifying chess as a sport and/or game, and classifying a tree house (which is agreed to be both a building and not a building!).
Classical concepts are transitive hierarchies, but actual categories may be intransitive [Murphy]
     Full Idea: The classical view of concepts explains hierarchical order, where categories form nested sets. But research shows that categories are often not transitive. Research shows that a seat is furniture, and a car seat is a seat, but it is not furniture.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: [compressed] Murphy adds that the nesting of definitions is classically used to match the nesting of hierarchies. This is a nice example of the neatness of the analytic philosopher breaking down when it meets the mess of the world.
The classical core is meant to be the real concept, but actually seems unimportant [Murphy]
     Full Idea: A problem with the revised classical view is that the concept core does not seem to be an important part of the concept, despite its name and theoretical intention as representing the 'real' concept.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: Apparently most researchers feel they can explain their results without reference to any core. Not so fast, I would say (being an essentialist). Maybe people acknowledge an implicit core without knowing what it is. See Susan Gelman.
18. Thought / D. Concepts / 4. Structure of Concepts / d. Concepts as prototypes
There is no 'ideal' bird or dog, and prototypes give no information about variability [Murphy]
     Full Idea: Is there really an 'ideal bird' that could represent all birds? ...Furthermore a single prototype would give no information about the variability of a category. ...Compare the incredible variety of dogs to the much smaller diversity of cats.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: The point about variability is particularly noteworthy. You only grasp the concept of 'furniture' when you understand its range, as well as its typical examples. What structure is needed in a concept to achieve this?
Prototypes are unified representations of the entire category (rather than of members) [Murphy]
     Full Idea: In the prototype view the entire category is represented by a unified representation rather than separate representations for each member, or for different classes of members.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: This is the improved prototype view, as opposed to the implausible idea that there is one ideal exemplar. The new theory still have the problem of how to represent diversity within the category, while somehow remaining 'unified'.
The prototype theory uses observed features, but can't include their construction [Murphy]
     Full Idea: Nothing in the prototype model says the shape of an animal is more important than its location in identifying its kind. The theory does not provide a way the features can be constructed, rather than just observed.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This makes some kind of mental modelling central to thought, and not just a bonus once you have empirically acquired the concepts. We bring our full range of experience to bear on even the most instantaneous observations.
The prototype theory handles hierarchical categories and combinations of concepts well [Murphy]
     Full Idea: The prototype view has no trouble with either hierarchical structure or explaining categories. ...Meaning and conceptual combination provide strong evidence for prototypes.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: Prototypes are not vague, making clearer classification possible. A 'mountain lion' is clear, because its components are clear.
Prototypes theory of concepts is best, as a full description with weighted typical features [Murphy]
     Full Idea: Our theory of concepts must be primarily prototype-based. That is, it must be a description of an entire concept, with its typical features (presumably weighted by their importance).
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This is to be distinguished from the discredited 'classical' view of concepts, that the concept consists of its definition. I take Aristotle's account of definition to be closer to a prototype description than to a dictionary definition.
Learning concepts is forming prototypes with a knowledge structure [Murphy]
     Full Idea: My proposal is that people attempt to form prototypes as part of a larger knowledge structure when they learn concepts.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This combines theory theory (knowledge) with the prototype view, and sounds rather persuasive. The formation of prototypes fits with the explanatory account of essentialism I am defending. He later calls prototype formation 'abstraction' (494).
18. Thought / D. Concepts / 4. Structure of Concepts / e. Concepts from exemplars
The most popular theories of concepts are based on prototypes or exemplars [Murphy]
     Full Idea: The most popular theories of concepts are based on prototype or exemplar theories that are strongly unclassical.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy]
     Full Idea: In the exemplar view of concepts, the idea that people have a representation that somehow encompasses an entire concept is rejected. ...Instead a person's concept of dogs is the set of dogs that the person remembers.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: [The theory was introduced by Medin and Schaffer 1978] I think I have finally met a plausible theory of concepts. When I think 'dog' I conjure up a fuzz of dogs that exhibit the range I have encountered (e.g. tiny to very big). Individuals come first!
The concept of birds from exemplars must also be used in inductions about birds [Murphy]
     Full Idea: We don't have one concept of birds formed by learning from exemplars, and another concept of birds that is used in induction.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: In other words exemplar concepts break down when we generalise using the concept. The exemplars must be unified, to be usable in thought and language.
Exemplar theory struggles with hierarchical classification and with induction [Murphy]
     Full Idea: The exemplar view has trouble with hierarchical classification and with induction in adults.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: To me these both strongly support essentialism - that you form the concept 'dog' from seeing some dogs, but you then extrapolate to large categories and general truths about dogs, on the assumption of the natures of the dogs you have seen.
Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy]
     Full Idea: The findings showing that children use knowledge and may be essentialist about category membership do not comport well with the exemplar view.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: Tricky, because Gelman persuaded me of the essentialism, but the exemplar view of concepts looks the most promising. Clearly they must be forced to coexist....
Conceptual combination must be compositional, and can't be built up from exemplars [Murphy]
     Full Idea: The exemplar accounts of conceptual combination are demonstrably wrong, because the meaning of a phrase has to be composed from the meaning of its parts (plus broader knowledge), and it cannot be composed as a function of exemplars.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This sounds quite persuasive, and I begin to see that my favoured essentialism fits the prototype view of concepts best, though this mustn't be interpreted too crudely. We change our prototypes with experience. 'Bird' is a tricky case.
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
We do not learn concepts in isolation, but as an integrated part of broader knowledge [Murphy]
     Full Idea: The knowledge approach argues that concepts are part of our general knowledge about the world. We do not learn concepts in isolation, ...but as part of our overall understanding of the world. Animal concepts are integrated with biology, behaviour etc.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: This is one of the leading theories of concepts among psychologists. It seems to be an aspect of the true theory, but it needs underpinning with some account of isolated individual concepts. This is also known as the 'theory theory'.
Concepts with familiar contents are easier to learn [Murphy]
     Full Idea: A concept's content influences how easy it is to learn. If the concept is grossly incompatible with what people know prior to the experiment, it will be difficult to acquire.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This is a preliminary fact which leads towards the 'knowledge' theory of concepts (aka 'theory theory'). The point being that the knowledge involved is integral to the concept. Fits my preferred mental files approach.
Some knowledge is involved in instant use of categories, other knowledge in explanations [Murphy]
     Full Idea: Some kinds of knowledge are probably directly incorporated into the category representation and used in normal, fast decisions about objects. Other kinds of knowledge, however, may come into play only when it has been solicited.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This is a summary of empirical research, but seems to fit our normal experience. If you see a hawk, you have some instant understanding, but if you ask what the hawk is doing here, you draw more widely.
People categorise things consistent with their knowledge, even rejecting some good evidence [Murphy]
     Full Idea: People tend to positively categorise items that are consistent with their knowledge and to exclude items that are inconsistent, sometimes even overruling purely empirical sources of information.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: The main rival to 'theory theory' is the purely empirical account of how concepts are acquired. This idea reports empirical research in favour of the theory theory (or 'knowledge') approach.
22. Metaethics / B. Value / 1. Nature of Value / b. Fact and value
Systems that generate a sense of value are basic to the primitive brain [Edelman/Tononi]
     Full Idea: Early and central in the development of the brain are the dimensions provided by value systems indicating salience for the entire organism.
     From: G Edelman / G Tononi (Consciousness: matter becomes imagination [2000], Ch.13)
     A reaction: This doesn't quite meet Hume's challenge to find values in the whole of nature, but it matches Charles Taylor's claim that for humans values are knowable a priori. Conditional values can be facts of the whole of nature. "If there is life, x has value..".
25. Social Practice / F. Life Issues / 6. Animal Rights
Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley]
     Full Idea: Hermarchus said that animal killing is justified by considerations of human safety and nourishment and by animals' inability to form contractual relations of justice with us.
     From: report of Hermarchus (fragments/reports [c.270 BCE]) by David A. Sedley - Hermarchus
     A reaction: Could the last argument be used to justify torturing animals? Or could we eat a human who was too brain-damaged to form contracts?