23 ideas
| 19404 | Necessities rest on contradiction, and contingencies on sufficient reason [Leibniz] |
| Full Idea: The principle of contradiction is the principle of necessity, and the principle that a sufficient reason must be given is the principle of contingency. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: [this paragraph is actually undated] Contradictions occur in concrete actuality, as well as in theories and formal systems. If so, then there are necessities in nature. Are they discoverable a posteriori? Leibniz says not. |
| 18877 | Moral realism doesn't seem to entail the existence of any things [Cameron] |
| Full Idea: Moral realism isn't realism about things, and it seems strange to suggest that moral realism is existence entailing in the way that realism about unobservable is. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Realism') | |
| A reaction: Cameron is questioning whether a realist has to believe in truthmakers. It seems to me that his doubts are because he insists that truthmaking is committed to the existence of 'things'. I assume any moral realism must supervene on nature. |
| 18868 | Surely if some propositions are grounded in existence, they all are? [Cameron] |
| Full Idea: What possible reason could one have for thinking of some propositions that they need to be grounded in what there is that doesn't apply to all propositions? | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: Well, if truthmaking said that all truths are grounded, then some could be grounded in what there is, and others in how it is, or maybe even how it isn't (if you get a decent account of negative truths). |
| 18867 | Orthodox Truthmaker applies to all propositions, and necessitates their truth [Cameron] |
| Full Idea: Orthodox truthmaker theory (Armstrong's) entails Maximalism (that every true proposition has at least one truthmaker), and Necessitarianism (that the existence of a truthmaker necessitates the truth of its proposition). | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: I think I accept both of these. If you say only some truths have truthmakers, the other truths are then baffling. And how could a truthmaker fail in its job? But that doesn't necessitate the existence of the proposition. |
| 18873 | God fixes all the truths of the world by fixing what exists [Cameron] |
| Full Idea: The truthmaker thought is that explanation only bottoms out at existence facts; for God to give a complete plan of the world He needs only make an inventory of what is to exist. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: He is defending Necessitarianism about truthmaking. I'm struggling with this. An inventory of the contents of my house doesn't begin to fix all the truths that arise from them. Why is Cameron so resistent to 'how' things are being part of the truthmaking? |
| 18879 | What the proposition says may not be its truthmaker [Cameron] |
| Full Idea: The explanation of the truth of the proposition [p] doesn't stop at it being the case that p, so it's false to claim that whenever a proposition is true it's true in virtue of the world being as the proposition says it is. The features often lie deeper. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Grounding') | |
| A reaction: [He is opposing Jennifer Hornsby 2005] Cameron offers 'the average family has 2.4 children' as a counterexample' (since no one actually has 2.4 children). That seems compelling. Second example: 'the rose is beautiful'. |
| 18880 | Rather than what exists, some claim that the truthmakers are ways of existence, dispositions, modalities etc [Cameron] |
| Full Idea: Rivals to the truthmaker claim that facts about what there is are the truthmakers, there are theories that add facts about how the things are, or add dispositional facts, or modal facts, or haecceitistic facts, or maybe moral facts. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Grounding') | |
| A reaction: [compressed] He seems to think his version has a monopoly on truthmaking, but I don't see why these other theories shouldn't count as truthmaking. The truthmaker for 'live grenades are dangerous' is not just the existence of grenades. |
| 18874 | Truthmaking doesn't require realism, because we can be anti-realist about truthmakers [Cameron] |
| Full Idea: It's definitely not sufficient to be a realist that one be a truthmaker theorist, since one can simply be anti-realist about the truthmakers. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Realism') | |
| A reaction: It is not quite clear how unreal truth makers could actually MAKE propositions true, rather than just being correlated with them. |
| 18869 | Without truthmakers, negative truths must be ungrounded [Cameron] |
| Full Idea: If negative truths don't have truthmakers then make no mistake: they are ungrounded. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: What would be the grounding for truths which expressed the necessary preconditions for all existence? Could 'nothing whatever exists' ever be a truth? |
| 18871 | I support the correspondence theory because I believe in truthmakers [Cameron] |
| Full Idea: I tend to think that the fundamental reason we can have the correspondence theory of truth is that truthmaker theory is correct. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: [This responds to Fumerton 2006, who gives the opposite view] Cameron gives himself the classic problem of spelling out the correspondence relation (perhaps as 'congruence'). I like truthmaking, but I'm unsure about correspondence. |
| 18870 | Maybe truthmaking and correspondence stand together, and are interdefinable [Cameron] |
| Full Idea: One view says truthmaker theory stands or falls with the correspondence theory of truth, because the truthmaker for p is just the portion of reality that p corresponds to: truthmaker and correspondence can be conversely defined. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: The normal view, which I prefer, is that correspondence is a particular theory of truthmaking, invoking a precise 'correspondence' relation. Hence abolishing correspondence would not abolish truthmaking, if you had a rival account. |
| 18881 | For realists it is analytic that truths are grounded in the world [Cameron] |
| Full Idea: The analytic commitment of realism is that truths are grounded in the world. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Grounding') | |
| A reaction: Certain fifth-level truths might be a long way from the actual world, and deeply interfused with human concepts and theories. Negative truths must be fitted into this picture. |
| 18875 | Realism says a discourse is true or false, and some of it is true [Cameron] |
| Full Idea: Realism about a discourse is 1) to think that the sentences are, when construed literally, literally true or false, and 2) to think that some of the sentences of the discourse are non-vacuously true. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Realism') | |
| A reaction: [Cameron adds 'non-vacuously' to an idea of Sayre-McCord 199 p.5] This is realism based on what is 'true', without specifying 'commitments', so I like it. Cameron says it makes mathematical postulationists into realists. He likes 'mind-independent'. |
| 18878 | Realism says truths rest on mind-independent reality; truthmaking theories are about which features [Cameron] |
| Full Idea: All that is necessary for realism, I claim, is that truth is grounded in mind-independent features of fundamental reality. Truthmaker theory comes into play because it is a theory about what those features are (…so it isn't a commitment to realism). | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Realism') | |
| A reaction: [He cites Michael Devitt for this approach] What is the word 'fundamental' doing here? Because the mind-dependent parts of reality are considered non-fundamental? The no-true-Scotsman-hates-whisky move? His truthmaking is committed to 'things'. |
| 18872 | We should reject distinct but indiscernible worlds [Cameron] |
| Full Idea: I think we should reject distinct but indiscernible worlds. | |
| From: Ross P. Cameron (Truthmakers, Realism and Ontology [2008], 'Max and Nec') | |
| A reaction: An interesting passing remark. Presumably there would be unknowable truths about such worlds, which wouldn't bother a full-blooded realist. Indiscernible to whom? Me? Humanity? A divine mind? |
| 22717 | Self-interest can fairly divide a cake; first person cuts, second person chooses [Poundstone] |
| Full Idea: To fairly divide a cake between two children, the first divides it and the second chooses. …Even division is best, as it anticipates the second child will take the largest piece. Fairness is enforced by the children's self-interests. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 03 'Cake') | |
| A reaction: [compressed] This is introduced as the basic principle of game theory. There is an online video of two cats sharing a dish of milk; each one drinks a bit, then pushes the dish to the other one. I'm sure two children could manage that. |
| 22718 | Formal game theory is about maximising or minimising numbers in tables [Poundstone] |
| Full Idea: At the most abstract level, game theory is about tables with numbers in them - numbers that entities are are efficiently acting to maximise or minimise. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 03 'Curve') | |
| A reaction: A brilliant idea. The question is the extent to which real life conforms to the numberical tables. The assumption that everyone is entirely self-seeking is blatantly false. Numbers like money have diminishing marginal utility. |
| 22719 | The minimax theorem says a perfect game of opposed people always has a rational solution [Poundstone] |
| Full Idea: The minimax theorem says that there is always a rational solution to a precisely defined conflict between two people whose interests are completely opposite. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 03 'Minimax') | |
| A reaction: This is Von Neumann's founding theorem of game theory. It concerns maximising minimums, and minimising maximums. Crucially, I would say that it virtually never occurs that two people have completely opposite interests. There is a common good. |
| 22720 | Two prisoners get the best result by being loyal, not by selfish betrayal [Poundstone] |
| Full Idea: Prisoners A and B can support or betray one another. If both support, they each get 1 year in prison. If one betrays, the betrayer gets 0 and the betrayed gets 3. If they both betray they get 2 each. The common good is to support each other. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 06 'Tucker's') | |
| A reaction: [by Albert Tucker, highly compressed] The classic Prisoner's Dilemma. It is artificial, but demonstrates that selfish behaviour gets a bad result (total of four years imprisonment), but the common good gets only two years. Every child should study this! |
| 22721 | The tragedy in prisoner's dilemma is when two 'nice' players misread each other [Poundstone] |
| Full Idea: The tragedy is when two 'nice' players defect because they misread the other's intentions. The puzzle of the prisoner's dilemma is how such good intentions pave the road to hell. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 11 'Howard's') | |
| A reaction: I really wish these simple ideas were better known. They more or less encapsulate the tragedy of the human race, with its inability to prioritise the common good. |
| 22722 | TIT FOR TAT says cooperate at first, then do what the other player does [Poundstone] |
| Full Idea: The successful TIT FOR TAT strategy (for the iterated prisoner's dilemma) says cooperate on the first round, then do whatever the other player did in the previous round. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 12 'TIT') | |
| A reaction: There are also the tougher TWO TITS FOR A TAT, and the more forgiving TIT FOR TWO TATS. The one-for-one seems to be the main winner, and is commonly seen in animal life (apparently). I recommend this to school teachers. |
| 22723 | Do unto others as you would have them do unto you - or else! [Poundstone] |
| Full Idea: TIT FOR TAT threatens 'Do unto others as you would have them do unto you - or else!'. | |
| From: William Poundstone (Prisoner's Dilemma [1992], 12 'TIT') | |
| A reaction: Essentially human happiness arises if we are all nice, but also stand up firmly for ourselves. 'Doormats' (nice all the time) get exploited. TIT FOR TAT is weak, because it doesn't exploit people who don't respond at all. |
| 19403 | Each of the infinite possible worlds has its own laws, and the individuals contain those laws [Leibniz] |
| Full Idea: As there are an infinity of possible worlds, there are also an infinity of laws, some proper to one, another to another, and each possible individual of any world contains in its own notion the laws of its world. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: Hence Leibniz is not really a scientific essentialist, in that he doesn't think the laws arise out of the nature of the matter consituting the world. I wonder if the primitive matter of bodies which attaches to the monads is the same in each world? |