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18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality

[general capacity for reason and logic]

27 ideas
Aristotle gives a superior account of rationality, because he allows emotions to participate [Hursthouse on Aristotle]
     Full Idea: Aristotle gives a superior account of human rationality, because he allows emotions to participate in reason, rather than being mere animal, non-rational impulses.
     From: comment on Aristotle (Nicomachean Ethics [c.334 BCE]) by Rosalind Hursthouse - On Virtue Ethics Intro
     A reaction: This is obviously helpful in virtue ethics, but it is a bit questionable, if the core of rationality is 'giving reasons'. A feeling might be a reason, but only once it has been conceptualised. "For RLS, his feelings were his reasons", said Henry James.
The rational part of the soul is the desire for truth, understanding and recollection [Galen]
     Full Idea: That part of the soul which we call rational is desiderative: …it desires truth, knowledge, learning, understanding, and recollection - in short, all the good things.
     From: Galen (The soul's dependence on the body [c.170], Kiv.2.772)
     A reaction: Truth is no surprise, but recollection is. Note the separation of knowledge from understanding. This is a very good characterisation of rationality. For the Greeks it has a moral dimension, of wanting what is good.
All thought is feeling, and rationality is the sensitive soul contemplating reasoning [La Mettrie]
     Full Idea: Thought is only a capacity to feel, and the rational soul is only the sensitive soul applied to the contemplation of ideas and to reasoning.
     From: Julien Offray de La Mettrie (Machine Man [1747], p.33)
     A reaction: What a very nice idea. La Mettrie wants to bring us closer to animals. Because we can pursue a train of rational thought, it does not follow that we have a faculty called 'rationality'. A dog can follow a clever series of clues that lead to food.
Kantian 'intuition' is the bridge between pure reason and its application to sense experiences [Kant, by Friend]
     Full Idea: In Kant's technical sense, 'intuition' is the bridge between sense experience and pure reasoning, making it possible for us to apply our reasoning to the physical world around us.
     From: report of Immanuel Kant (Critique of Pure Reason [1781]) by Michèle Friend - Introducing the Philosophy of Mathematics 3.3
     A reaction: Although this concept invites Ockham's Razor, I like it, since it focuses on the mystery of how reasoning can have application. It is the bridge between the analytic and the synthetic, between the a priori and the empirical. It unites thought.
When absorbed in deep reflection, is your reason in control, or is it you? [Feuerbach]
     Full Idea: When, submerged in deep reflection, you forget both yourself and your surroundings, is it you who controls reason, or is it rather reason that controls and absorbs you?
     From: Ludwig Feuerbach (Introduction of 'Essence of Christianity' [1841], I)
     A reaction: A delightful question, even if it looks like a false dichotomy. I'm not sure what to make of 'me', if my reason can be subtracted from it. Aquinas was one the same wavelength here.
Reasoning involves observation, experiment, and habituation [Peirce]
     Full Idea: The mental operations concerning in reasoning are three. The first is Observation; the second is Experimentation; and the third is Habituation.
     From: Charles Sanders Peirce (Reasoning and the Logic of Things [1898], V)
     A reaction: I like the breadth of this. Even those who think scientific reasoning has priority over logic (as I do, thinking of it as the evaluation of evidence, with Sherlock Holmes as its role model) will be surprised to finding observation and habituation there.
Rationality is a scheme we cannot cast away [Nietzsche]
     Full Idea: Thinking rationally is interpreting according to a scheme we cannot cast away.
     From: Friedrich Nietzsche (Writings from Late Notebooks [1887], 05[22])
     A reaction: We can turn the tables on this one: how could Nietzsche know that this is the case if he cannot criticise his own rationality? The brain is a truth machine, and truth is (mostly) vital for survival.
How can the ground of rationality be itself rational? [James]
     Full Idea: Can that which is the ground of rationality in all else be itself properly called rational?
     From: William James (The Sentiment of Rationality [1882], p.25)
     A reaction: This is the perennial problem in deciding grounds, and in deciding what to treat as primitive. The stoics see the whole of nature as rational. Cf how can the ground of what is physical be itself physical?
It is rational to believe in reality, despite the lack of demonstrative reasons for it [Russell]
     Full Idea: In the preceding chapter we agreed, though without being able to find demonstrative reasons, that it is rational to believe that our sense-data are signs of an independent reality.
     From: Bertrand Russell (Problems of Philosophy [1912], Ch. 3)
     A reaction: I wonder if Russell was the first to grasp this essential distinction. I suspect that three hundred years (1600-1900) were wasted in philosophy because they thought that everything rational had to be demonstrable. E.g. Hume on induction.
Absence of all rationality would be absence of thought [Davidson]
     Full Idea: To imagine a totally irrational animal is to imagine an animal without thought.
     From: Donald Davidson (Davidson on himself [1994], p.232)
     A reaction: This wouldn't be so clear without the theory of evolution, which suggests that only the finders of truth last long enough to breed.
Ordinary rationality is conservative, starting from where your beliefs currently are [Harman]
     Full Idea: Ordinary rationality is generally conservative, in the sense that you start from where you are, with your present beliefs and intentions.
     From: Gilbert Harman (Rationality [1995], 1.3)
     A reaction: This stands opposed to the Cartesian or philosophers' rationality, which requires that (where possible) everything be proved from scratch. Harman seems right, that the normal onus of proof is on changing beliefs, rather proving you should retain them.
Rationality is normally said to concern either giving reasons, or reliability [Nozick]
     Full Idea: The two themes permeating the philosophical literature are that rationality is a matter of reasons, or that rationality is a matter of reliability.
     From: Robert Nozick (The Nature of Rationality [1993], p.64)
     A reaction: Since a clock can be reliable, I would have thought it concerns reasons. Or an unthinking person could reliably recite truths from memory. There is also the instrumental view of rationality.
In the instrumental view of rationality it only concerns means, and not ends [Nozick]
     Full Idea: On the instrumental conception of rationality, it consists in the effective and efficient achievement of goals, ends, and desires. About the goals themselves it has little to say.
     From: Robert Nozick (The Nature of Rationality [1993], p.64)
     A reaction: [He quotes Russell 1954 p.viii as expressing this view] A long way from Greek logos, which obviously concerns the rational selection of right ends (for which, presumably, reasons can be given). In practice our ends may never be rational, of course.
Is it rational to believe a truth which leads to permanent misery? [Nozick]
     Full Idea: If a mother is presented with convincing evidence that her son has committed a grave crime, but were she to believe it that would make her life thereafter miserable, is it rational for her to believe her son is guilty?
     From: Robert Nozick (The Nature of Rationality [1993], p.69)
     A reaction: I assume there is a conflict of rationalities, because there are conflicting ends. Presumably most mothers love the truth, but most of us also aim for happy lives. It is perfectly rational to avoid discovering a horrible family truth.
Rationality needs some self-consciousness, to also evaluate how we acquired our reasons [Nozick]
     Full Idea: Rationality involves some degree of self-consciousness. Not only reasons are evaluated, but also the processes by which information arrives, is stored, and recalled.
     From: Robert Nozick (The Nature of Rationality [1993], p.74)
     A reaction: I defend the idea that animals have a degree of rationality, because they can make sensible judgements, but I cannot deny this idea. Rationality comes in degrees, and second-level thought is a huge leap forward in degree.
Rationality has mental properties - autonomy, productivity, experiment [Fodor]
     Full Idea: Mentalism isn't gratuitous; you need it to explain rationality. Mental causation buys you behaviours that are unlike reflexes in at least three ways: they're autonomous, they're productive, and they're experimental.
     From: Jerry A. Fodor (The Elm and the Expert [1993], §4)
     A reaction: He makes his three ways sound all-or-nothing, which is (I believe) the single biggest danger when thinking about the mind. "Either you are conscious, or you are not..."
Only rational beings are attentive without motive or concern [Scruton]
     Full Idea: It is only rational beings who can be attentive without a motive; only rational beings who can be interested in that in which they have no interest.
     From: Roger Scruton (Laughter [1982], §12)
     A reaction: Rational beings make long term plans, so they cannot prejudge which things may turn out to be of interest to them. Scruton (a Kantian) makes it sound a little loftier than it actually is.
Capturing all the common sense facts about rationality is almost impossible [Smith,M]
     Full Idea: It would be a superhuman task just to write down an explicit, non-summary style, statement of the platitudes that capture our idea of what it is to be fully rational.
     From: Michael Smith (The Moral Problem [1994], 5.9)
     A reaction: Well said. Philosophers are inclined to make simplistic binary judgements about whether persons or animals are rational. A visit to YouTube will show fish acting extremely rationally.
Stich accepts eliminativism (labelled 'pragmatism') about rationality and normativity [Stich, by Engel]
     Full Idea: Stich accepts a form of eliminativism (which he calls 'pragmatism') about rationality and normativity generally.
     From: report of Stephen P. Stich (The Fragmentation of Reason [1990]) by Pascal Engel - Truth §5.3
     A reaction: This seems to be the correct position for a Humean empiricist connectionist. Presumably he has some good reasons for eliminating rationality.
Consistency is the cornerstone of rationality [Baggini /Fosl]
     Full Idea: Consistency is the cornerstone of rationality.
     From: J Baggini / PS Fosl (The Philosopher's Toolkit [2003], §1.06)
     A reaction: This is right, and is a cornerstone of Kant's approach to ethics. Rational beings must follow principles - in order to be consistent in their behaviour. 'Consistent' now requires a definition….
Kantian principled rationality is recognition of a priori universal truths [Hanna]
     Full Idea: The 'principled' (Kantian) sense of rationality means the possession of a capacity for generating or recognizing necessary truths, a priori beliefs, strictly universal normative rules, nonconsequentialist moral obligations, and categorical 'ought' claims.
     From: Robert Hanna (Rationality and Logic [2006], Intro)
Hegelian holistic rationality is the capacity to seek coherence [Hanna]
     Full Idea: The 'holistic' (Hegelian) sense of rationality means the capacity for systematically seeking coherence (or 'reflective equilibrium') across a network or web of beliefs, desires, emotions, intentions and volitions. Traditionally 'the truth is the whole'.
     From: Robert Hanna (Rationality and Logic [2006], Intro)
     A reaction: On the whole this is my preferred view (which sounds Quinean as well as Hegelian), though I reject the notion that truth is a whole. I take coherence to be the hallmark of justification, though not of truth, and reason aims to justify.
Humean Instrumental rationality is the capacity to seek contingent truths [Hanna]
     Full Idea: The 'instrumental' (Humean) sense of rationality means a capacity for generating or recognizing contingent truths, contextually normative rules, consequentialist obligations, and hypothetical 'ought' claims. Reason is 'the slave of the passions'.
     From: Robert Hanna (Rationality and Logic [2006], Intro)
Rational animals have a normative concept of necessity [Hanna]
     Full Idea: A rational animal is one that is a normative-reflective possessor of the concepts of necessity, certainty and unconditional obligation.
     From: Robert Hanna (Rationality and Logic [2006], 4.0)
     A reaction: The addition of obligation shows the Kantian roots of this. It isn't enough just to possess a few concepts. You wouldn't count as rational if you didn't desire truth, as well as understanding it. Robots be warned.
One tradition says talking is the essence of rationality; the other says the essence is logic [Hanna]
     Full Idea: In the tradition of Descartes, Chomsky and Davidson, rational animals are essentially talking animals. But in the view of Kant, and perhaps Fodor, it is the cognitive capacity for logic that is the essence of human rationality.
     From: Robert Hanna (Rationality and Logic [2006], 4.9)
Rationality is conformity to reasons that can be sustained even after scrutiny [Sen]
     Full Idea: My main argument can be fairly easily understood in terms of seeing rationality as conformity with reasons that one can sustain, even after scrutiny, and not just at first sight.
     From: Amartya Sen (The Idea of Justice [2009], 08 'Rational' n)
     A reaction: We would need to say more about the 'scrutiny' before we had a really good account of rationality here. In Idea 20982 he emphasises the need for scrutiny by other people, and not mere self-criticism. The key may to be invite outside criticism.
No one has yet devised a rationality test [New Sci.]
     Full Idea: The financial sector has been clamouring for a rationality test for years.
     From: New Scientist writers (New Scientist articles [2013], 2013.10.29)
     A reaction: Many aspects of intelligence tests do actually pick out what I would call rationality (which includes 'rational intuition', a new favourite of mine). But they are mixed in with rather mechanical geeky sort of tests.