31 ideas
| 19395 | Philosophy is sanctified, because it flows from God [Leibniz] |
| Full Idea: Philosophy is sanctified by having its streams flow from the fountain of God's attributes. | |
| From: Gottfried Leibniz (A General Principle to Explain Laws of Nature [1687], p.69) |
| 18806 | Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt] |
| Full Idea: Frege rejected the traditional categories as importing psychological and linguistic impurities into logic. | |
| From: report of Gottlob Frege (Function and Concept [1891]) by Ian Rumfitt - The Boundary Stones of Thought 1.2 | |
| A reaction: Resisting such impurities is the main motivation for making logic entirely symbolic, but it doesn't follow that the traditional categories have to be dropped. |
| 8490 | First-level functions have objects as arguments; second-level functions take functions as arguments [Frege] |
| Full Idea: Just as functions are fundamentally different from objects, so also functions whose arguments are and must be functions are fundamentally different from functions whose arguments are objects. The latter are first-level, the former second-level, functions. | |
| From: Gottlob Frege (Function and Concept [1891], p.38) | |
| A reaction: In 1884 he called it 'second-order'. This is the standard distinction between first- and second-order logic. The first quantifies over objects, the second over intensional entities such as properties and propositions. |
| 8492 | Relations are functions with two arguments [Frege] |
| Full Idea: Functions of one argument are concepts; functions of two arguments are relations. | |
| From: Gottlob Frege (Function and Concept [1891], p.39) | |
| A reaction: Nowadays we would say 'two or more'. Another interesting move in the aim of analytic philosophy to reduce the puzzling features of the world to mathematical logic. There is, of course, rather more to some relations than being two-argument functions. |
| 8487 | Arithmetic is a development of logic, so arithmetical symbolism must expand into logical symbolism [Frege] |
| Full Idea: I am of the opinion that arithmetic is a further development of logic, which leads to the requirement that the symbolic language of arithmetic must be expanded into a logical symbolism. | |
| From: Gottlob Frege (Function and Concept [1891], p.30) | |
| A reaction: This may the the one key idea at the heart of modern analytic philosophy (even though logicism may be a total mistake!). Logic and arithmetical foundations become the master of ontology, instead of the servant. The jury is out on the whole enterprise. |
| 18899 | Frege takes the existence of horses to be part of their concept [Frege, by Sommers] |
| Full Idea: Frege regarded the existence of horses as a property of the concept 'horse'. | |
| From: report of Gottlob Frege (Function and Concept [1891]) by Fred Sommers - Intellectual Autobiography 'Realism' |
| 4028 | Frege allows either too few properties (as extensions) or too many (as predicates) [Mellor/Oliver on Frege] |
| Full Idea: Frege's theory of properties (which he calls 'concepts') yields too few properties, by identifying coextensive properties, and also too many, by letting every predicate express a property. | |
| From: comment on Gottlob Frege (Function and Concept [1891]) by DH Mellor / A Oliver - Introduction to 'Properties' §2 | |
| A reaction: Seems right; one extension may have two properties (have heart/kidneys), two predicates might express the same property. 'Cutting nature at the joints' covers properties as well as objects. |
| 8489 | The concept 'object' is too simple for analysis; unlike a function, it is an expression with no empty place [Frege] |
| Full Idea: I regard a regular definition of 'object' as impossible, since it is too simple to admit of logical analysis. Briefly: an object is anything that is not a function, so that an expression for it does not contain any empty place. | |
| From: Gottlob Frege (Function and Concept [1891], p.32) | |
| A reaction: Here is the core of the programme for deriving our ontology from our logic and language, followed through by Russell and Quine. Once we extend objects beyond the physical, it becomes incredibly hard to individuate them. |
| 19394 | Inequality can be brought infinitely close to equality [Leibniz] |
| Full Idea: Equality may be considered as an infinitely small inequality, and we may make inequality approach equality as much as we wish. | |
| From: Gottfried Leibniz (A General Principle to Explain Laws of Nature [1687], p.67) | |
| A reaction: An interesting response to David Lewis's brusque dismissal of the problem of identity, as all-or-nothing...end of story. |
| 9240 | Love creates a necessity concerning what to care about [Frankfurt] |
| Full Idea: The necessity with which love binds the will puts an end to indecisiveness concerning what to care about. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.13) | |
| A reaction: I put this here as a reminder that there may be more to necessity than the dry concept of metaphysicians and logicians. 'Why did you rescue that man first?' 'Because I love him'. Kit Fine recognises many sorts of necessity. |
| 9947 | Concepts are the ontological counterparts of predicative expressions [Frege, by George/Velleman] |
| Full Idea: Concepts, for Frege, are the ontological counterparts of predicative expressions. | |
| From: report of Gottlob Frege (Function and Concept [1891]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.2 | |
| A reaction: That sounds awfully like what many philosophers call 'universals'. Frege, as a platonist (at least about numbers), I would take to be in sympathy with that. At least we can say that concepts seem to be properties. |
| 10319 | An assertion about the concept 'horse' must indirectly speak of an object [Frege, by Hale] |
| Full Idea: Frege had a notorious difficulty over the concept 'horse', when he suggests that if we wish to assert something about a concept, we are obliged to proceed indirectly by speaking of an object that represents it. | |
| From: report of Gottlob Frege (Function and Concept [1891], Ch.2.II) by Bob Hale - Abstract Objects | |
| A reaction: This sounds like the thin end of a wedge. The great champion of objects is forced to accept them here as a façon de parler, when elsewhere they have ontological status. |
| 8488 | A concept is a function whose value is always a truth-value [Frege] |
| Full Idea: A concept in logic is closely connected with what we call a function. Indeed, we may say at once: a concept is a function whose value is always a truth-value. ..I give the name 'function' to what is meant by the 'unsaturated' part. | |
| From: Gottlob Frege (Function and Concept [1891], p.30) | |
| A reaction: So a function becomes a concept when the variable takes a value. Problems arise when the value is vague, or the truth-value is indeterminable. |
| 9948 | Unlike objects, concepts are inherently incomplete [Frege, by George/Velleman] |
| Full Idea: For Frege, concepts differ from objects in being inherently incomplete in nature. | |
| From: report of Gottlob Frege (Function and Concept [1891]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.2 | |
| A reaction: This is because they are 'unsaturated', needing a quantified variable to complete the sentence. This could be a pointer towards Quine's view of properties, as simply an intrinsic feature of predication about objects, with no separate identity. |
| 4972 | I may regard a thought about Phosphorus as true, and the same thought about Hesperus as false [Frege] |
| Full Idea: From sameness of meaning there does not follow sameness of thought expressed. A fact about the Morning Star may express something different from a fact about the Evening Star, as someone may regard one as true and the other false. | |
| From: Gottlob Frege (Function and Concept [1891], p.14) | |
| A reaction: This all gets clearer if we distinguish internalist and externalist theories of content. Why take sides on this? Why not just ask 'what is in the speaker's head?', 'what does the sentence mean in the community?', and 'what is the corresponding situation?' |
| 9228 | Ranking order of desires reveals nothing, because none of them may be considered important [Frankfurt] |
| Full Idea: Ranking desires in order of preference is no help, because a person who wants one thing more than another may not regard the former as any more important to him than the latter. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.5) | |
| A reaction: A salutary warning. Someone may pursue something with incredible intensity, but only to stave off a boring and empty existence. The only way I can think of to assess what really matters to people is - to ask them! |
| 9238 | Morality isn't based on reason; moral indignation is quite unlike disapproval of irrationality [Frankfurt] |
| Full Idea: The ultimate warrant for moral principles cannot be found in reason. The sort of opprobrium that attaches to moral transgressions is quite unlike the sort of opprobrium that attaches to the requirements of reason. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.5 n6) | |
| A reaction: More like a piece of evidence than a proper argument. We may not feel indignant if someone fails a maths exam, but we might if they mess up the arithmetic of our bank account, even though they meant well. |
| 9234 | If you don't care about at least one thing, you can't find reasons to care about anything [Frankfurt] |
| Full Idea: It is not possible for a person who does not already care at least about something to discover reasons for caring about anything. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.11) | |
| A reaction: This is the key idea of this lovely book. Without a glimmer of love somewhere, it is not possible to bootstrap a meaningful life. The glimmer of caring about one thing is transferable. See the Ancient Mariner and the watersnake. |
| 9232 | It is by caring about things that we infuse the world with importance [Frankfurt] |
| Full Idea: It is by caring about things that we infuse the world with importance. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.10) | |
| A reaction: This book is a lovely attempt at getting to the heart of where values come from. 'Football isn't a matter of life and death; it's more important than that' - Bill Shankly (manager of Liverpool). Frankfurt is right. |
| 9233 | Our criteria for evaluating how to live offer an answer to the problem [Frankfurt] |
| Full Idea: Identifying the criteria to be employed in evaluating various ways of living is also tantamount to providing an answer to the question of how to live. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.10) | |
| A reaction: Presumably critical reflection is still possible about those criteria, even though he implies that they just arise out of you (in a rather Nietzschean way). The fear is that critical reflection on basic criteria kills in infant in its cradle. |
| 9229 | What is worthwhile for its own sake alone may be worth very little [Frankfurt] |
| Full Idea: What is worth having or worth doing for its own sake alone may nonetheless be worth very little. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.5) | |
| A reaction: That is one of my cherished notions sunk without trace! Aristotle's idea that ends are what matter, not means, always struck me as crucial. But Frankfurt is right. Collecting trivia is done for its own sake. Great tasks are performed as a means. |
| 9235 | Rather than loving things because we value them, I think we value things because we love them [Frankfurt] |
| Full Idea: It is often understood that we begin loving things because we are struck by their value. ..However, what I have in mind is rather that what we love necessarily acquires value for us because we love it. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.3) | |
| A reaction: The uneasy thought here is that this makes value much less rational. If you love because you value, you could probably give reasons for the value. If love comes first it must be instinctive. He says he loved his children before they were born. |
| 9237 | The paradigm case of pure love is not romantic, but that between parents and infants [Frankfurt] |
| Full Idea: Relationships that are primarily romantic or sexual do not provide very authentic or illuminating paradigms of love. ...The love of parents for their small children comes closest to offering recognizably pure instances of love. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.4) | |
| A reaction: Excellent. Though perhaps a relationships which began romantically might settle into something like the more 'pure' love that he has in mind. Such a relationship must, I trust, be possible between adults. |
| 9239 | I value my children for their sake, but I also value my love for them for its own sake [Frankfurt] |
| Full Idea: Beside the fact that my children are important to me for their own sakes, there is the additional fact that loving my children is important to me for its own sake. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.7) | |
| A reaction: This is at the heart of Frankfurt's thesis, that love is the bedrock of our values in life, and we therefore all need to love in order to generate any values in our life, quite apart from what our love is directed at. Nice thought. |
| 9236 | Love can be cool, and it may not involve liking its object [Frankfurt] |
| Full Idea: It is not among the defining features of love that it must be hot rather than cool, ..and nor is it essential that a person like what he loves. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.4) | |
| A reaction: An interesting pair of observations. The greatness of love would probably be measured by length, or by sacrifice. Extreme heat makes us a little suspicious. It would be hard to love something that was actually disliked. |
| 9227 | We might not choose a very moral life, if the character or constitution was deficient [Frankfurt] |
| Full Idea: People who are scrupulously moral may nonetheless be destined by deficiencies of character or of constitution to lead lives that no reasonable person would freely choose. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.2) | |
| A reaction: This fairly firmly refutes any Greek dream that all there is to happiness is leading a virtuous life. Frankfurt is with Aristotle more than with the Stoics. It would be tempting to sacrifice virtue to get a sunny character and good health. |
| 9230 | People want to fulfill their desires, but also for their desires to be sustained [Frankfurt] |
| Full Idea: Besides wanting to fulfil his desire, the person who cares about what he desires wants something else as well: he wants the desire to be sustained. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.6) | |
| A reaction: Plato, in 'Gorgias', makes this fact sound like a nightmare, resembling drug addiction, but in Frankfurt's formulation it looks like a good thing. If you want to make your family happy because you love them, you would dread finding your love had died. |
| 9241 | Loving oneself is not a failing, but is essential to a successful life [Frankfurt] |
| Full Idea: Far from demonstrating a flaw in character or being a sign of weakness, coming to love oneself is the deepest and most essential - and by no means the most readily attainable - achievement of a serious and successful life. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.14) | |
| A reaction: Obviously it will be necessary to dilineate the healthy form of self-love, which Frankfurt attempts to do. Ruthless vanity and self-seeking certainly look like the worst possible weaknesses of character. With that proviso, he is right. |
| 9300 | Boredom is serious, not just uncomfortable; it threatens our psychic survival [Frankfurt] |
| Full Idea: Boredom is a serious matter. It is not a condition that we seek to avoid just because we do not find it enjoyable. ..It threatens the very continuation of conscious mental life. ..Avoiding bored is a primitive urge for psychic survival. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 2.8) | |
| A reaction: Presumably nihilism will flood into the emptiness created by boredom. Frankfurt will see it as a lack of love for anything in your life, and hence an absence of value. Frankfurt is very good. |
| 9231 | Freedom needs autonomy (rather than causal independence) - embracing our own desires and choices [Frankfurt] |
| Full Idea: What counts as far as freedom goes is not causal independence, but autonomy. It is a matter of whether we are active rather than passive in our motives and choices, whether those are what we really want, and not alien to us. | |
| From: Harry G. Frankfurt (The Reasons of Love [2005], 1.8) | |
| A reaction: This is why setting your own targets is excellent, but having targets set for you by authorities is pernicious. These kind of principles need to be clear before any plausible theory of liberalism can be developed. |
| 8491 | The Ontological Argument fallaciously treats existence as a first-level concept [Frege] |
| Full Idea: The ontological proof of God's existence suffers from the fallacy of treating existence as a first-level concept. | |
| From: Gottlob Frege (Function and Concept [1891], p.38 n) | |
| A reaction: [See Idea 8490 for first- and second-order functions] This is usually summarised as the idea that existence is a quantifier rather than a predicate. |