140 ideas
19693 | There is practical wisdom (for action), and theoretical wisdom (for deep understanding) [Aristotle, by Whitcomb] |
3722 | Metaphysics goes beyond the empirical, so doesn't need examples [Kant] |
1575 | For Aristotle logos is essentially the ability to talk rationally about questions of value [Roochnik on Aristotle] |
3738 | The hallmark of rationality is setting itself an end [Kant] |
1589 | Aristotle is the supreme optimist about the ability of logos to explain nature [Roochnik on Aristotle] |
8200 | Aristotelian definitions aim to give the essential properties of the thing defined [Aristotle, by Quine] |
4385 | Aristotelian definition involves first stating the genus, then the differentia of the thing [Aristotle, by Urmson] |
13689 | 'Theorems' are formulas provable from no premises at all [Sider] |
13705 | Truth tables assume truth functionality, and are just pictures of truth functions [Sider] |
13706 | Intuitively, deontic accessibility seems not to be reflexive, but to be serial [Sider] |
13710 | In D we add that 'what is necessary is possible'; then tautologies are possible, and contradictions not necessary [Sider] |
13711 | System B introduces iterated modalities [Sider] |
13708 | S5 is the strongest system, since it has the most valid formulas, because it is easy to be S5-valid [Sider] |
13712 | Epistemic accessibility is reflexive, and allows positive and negative introspection (KK and K¬K) [Sider] |
13714 | We can treat modal worlds as different times [Sider] |
13720 | Converse Barcan Formula: □∀αφ→∀α□φ [Sider] |
13718 | The Barcan Formula ∀x□Fx→□∀xFx may be a defect in modal logic [Sider] |
13723 | System B is needed to prove the Barcan Formula [Sider] |
13715 | You can employ intuitionist logic without intuitionism about mathematics [Sider] |
13282 | Aristotle relativises the notion of wholeness to different measures [Aristotle, by Koslicki] |
13678 | The most popular account of logical consequence is the semantic or model-theoretic one [Sider] |
13679 | Maybe logical consequence is more a matter of provability than of truth-preservation [Sider] |
13682 | Maybe logical consequence is impossibility of the premises being true and the consequent false [Sider] |
13680 | Maybe logical consequence is a primitive notion [Sider] |
13722 | A 'theorem' is an axiom, or the last line of a legitimate proof [Sider] |
4730 | For Aristotle, the subject-predicate structure of Greek reflected a substance-accident structure of reality [Aristotle, by O'Grady] |
13696 | When a variable is 'free' of the quantifier, the result seems incapable of truth or falsity [Sider] |
13700 | A 'total' function must always produce an output for a given domain [Sider] |
13703 | λ can treat 'is cold and hungry' as a single predicate [Sider] |
13688 | Good axioms should be indisputable logical truths [Sider] |
13687 | No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider] |
13690 | Proof by induction 'on the length of the formula' deconstructs a formula into its accepted atoms [Sider] |
13691 | Induction has a 'base case', then an 'inductive hypothesis', and then the 'inductive step' [Sider] |
13685 | Natural deduction helpfully allows reasoning with assumptions [Sider] |
13686 | We can build proofs just from conclusions, rather than from plain formulae [Sider] |
13697 | Valuations in PC assign truth values to formulas relative to variable assignments [Sider] |
13684 | The semantical notion of a logical truth is validity, being true in all interpretations [Sider] |
13704 | It is hard to say which are the logical truths in modal logic, especially for iterated modal operators [Sider] |
13724 | In model theory, first define truth, then validity as truth in all models, and consequence as truth-preservation [Sider] |
13698 | In a complete logic you can avoid axiomatic proofs, by using models to show consequences [Sider] |
13699 | Compactness surprisingly says that no contradictions can emerge when the set goes infinite [Sider] |
13701 | A single second-order sentence validates all of arithmetic - but this can't be proved axiomatically [Sider] |
13692 | A 'precisification' of a trivalent interpretation reduces it to a bivalent interpretation [Sider] |
13695 | Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider] |
13693 | A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider] |
13694 | We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider] |
13683 | A relation is a feature of multiple objects taken together [Sider] |
13276 | The unmoved mover and the soul show Aristotelian form as the ultimate mereological atom [Aristotle, by Koslicki] |
13277 | The 'form' is the recipe for building wholes of a particular kind [Aristotle, by Koslicki] |
13702 | The identity of indiscernibles is necessarily true, if being a member of some set counts as a property [Sider] |
13721 | 'Strong' necessity in all possible worlds; 'weak' necessity in the worlds where the relevant objects exist [Sider] |
13707 | Maybe metaphysical accessibility is intransitive, if a world in which I am a frog is impossible [Sider] |
13709 | Logical truths must be necessary if anything is [Sider] |
13716 | 'If B hadn't shot L someone else would have' if false; 'If B didn't shoot L, someone else did' is true [Sider] |
13717 | Transworld identity is not a problem in de dicto sentences, which needn't identify an individual [Sider] |
13719 | Barcan Formula problem: there might have been a ghost, despite nothing existing which could be a ghost [Sider] |
5991 | For Aristotle, knowledge is of causes, and is theoretical, practical or productive [Aristotle, by Code] |
11239 | The notion of a priori truth is absent in Aristotle [Aristotle, by Politis] |
3726 | The categorical imperative is a practical synthetic a priori proposition [Kant] |
23312 | Aristotle is a rationalist, but reason is slowly acquired through perception and experience [Aristotle, by Frede,M] |
16111 | Aristotle wants to fit common intuitions, and therefore uses language as a guide [Aristotle, by Gill,ML] |
16971 | Plato says sciences are unified around Forms; Aristotle says they're unified around substance [Aristotle, by Moravcsik] |
11243 | Aristotelian explanations are facts, while modern explanations depend on human conceptions [Aristotle, by Politis] |
3320 | Aristotle's standard analysis of species and genus involves specifying things in terms of something more general [Aristotle, by Benardete,JA] |
12000 | Aristotle regularly says that essential properties explain other significant properties [Aristotle, by Kung] |
3739 | Free will is a kind of causality which works independently of other causes [Kant] |
3741 | We shall never be able to comprehend how freedom is possible [Kant] |
3740 | We cannot conceive of reason as being externally controlled [Kant] |
5296 | Kant made the political will into a pure self-determined "free" will [Kant, by Marx/Engels] |
24011 | Kant thought emotions are too random and passive to be part of morality [Kant, by Williams,B] |
23300 | Aristotle and the Stoics denied rationality to animals, while Platonists affirmed it [Aristotle, by Sorabji] |
11240 | The notion of analytic truth is absent in Aristotle [Aristotle, by Politis] |
5074 | Kant united religion and philosophy, by basing obedience to law on reason instead of faith [Taylor,R on Kant] |
8024 | The categorical imperative says nothing about what our activities and ends should be [MacIntyre on Kant] |
6559 | Aristotle never actually says that man is a rational animal [Aristotle, by Fogelin] |
22390 | Kant thought human nature was pure hedonism, so virtue is only possible via the categorical imperative [Foot on Kant] |
9750 | We must only value what others find acceptable [Kant, by Korsgaard] |
20160 | Kant focuses exclusively on human values, and neglects cultural and personal values [Kekes on Kant] |
9749 | Our rational choices confer value, arising from the sense that we ourselves are important [Kant, by Korsgaard] |
7671 | Values are created by human choices, and are not some intrinsic quality, out there [Kant, by Berlin] |
3720 | We may claim noble motives, but we cannot penetrate our secret impulses [Kant] |
3717 | Reverence is awareness of a value which demolishes my self-love [Kant] |
3712 | A good will is not good because of what it achieves [Kant] |
3725 | The good of an action is in the mind of the doer, not the consequences [Kant] |
3733 | The 'golden rule' cannot be a universal law as it implies no duties [Kant] |
3736 | Virtue lets a rational being make universal law, and share in the kingdom of ends [Kant] |
3544 | Kant thinks virtue becomes passive, and hence morally unaccountable [Kant, by Annas] |
7674 | Generosity and pity are vices, because they falsely imply one person's superiority to another [Kant, by Berlin] |
21029 | Kantian respect is for humanity and reason (not from love or sympathy or solidarity) [Kant, by Sandel] |
7105 | If 'maxims' are deeper underlying intentions, Kant can be read as a virtue theorist [Kant, by Statman] |
7625 | We can ask how rational goodness is, but also why is rationality good [Putnam on Kant] |
4024 | Kant follows Rousseau in defining freedom and morality in terms of each other [Taylor,C on Kant] |
3715 | Other causes can produce nice results, so morality must consist in the law, found only in rational beings [Kant] |
20715 | It is basic that moral actions must be done from duty [Kant] |
3710 | The only purely good thing is a good will [Kant] |
3737 | The will is good if its universalised maxim is never in conflict with itself [Kant] |
3718 | Telling the truth from duty is quite different from doing so to avoid inconvenience [Kant] |
3723 | There are no imperatives for a holy will, as the will is in harmony with moral law [Kant] |
3724 | A categorical imperative sees an action as necessary purely for its own sake [Kant] |
3735 | Men are subject to laws which are both self-made and universal [Kant] |
3714 | Dutiful actions are judged not by purpose, but by the maxim followed [Kant] |
5295 | Kant was happy with 'good will', even if it had no result [Kant, by Marx/Engels] |
6695 | Kant has to attribute high moral worth to some deeply unattractive human lives [Kant, by Graham] |
8028 | Kantian duty seems to imply conformism with authority [MacIntyre on Kant] |
8026 | Almost any precept can be consistently universalized [MacIntyre on Kant] |
15673 | The intuition behind the categorical imperative is that one ought not to make an exception of oneself [Kant, by Finlayson] |
8068 | Universalising a maxim needs to first stipulate the right description for the action [Anscombe on Kant] |
8025 | The categorical imperative will not suggest maxims suitable for testing [MacIntyre on Kant] |
8027 | I can universalize a selfish maxim, if it is expressed in a way that only applies to me [MacIntyre on Kant] |
3728 | Suicide, false promises, neglected talent, and lack of charity all involve contradictions of principle [Kant, by PG] |
22008 | Always treat yourself and others as an end, and never simply as a means [Kant] |
22009 | Morality is the creation of the laws that enable a Kingdom of Ends [Kant] |
3719 | If lying were the universal law it would make promises impossible [Kant] |
3762 | Why couldn't all rational beings accept outrageously immoral rules of conduct? [Mill on Kant] |
4413 | The categorical imperative smells of cruelty [Nietzsche on Kant] |
3716 | Act according to a maxim you can will as a universal law [Kant] |
3727 | Act as if your maxim were to become a universal law of nature [Kant] |
22050 | The maxim of an action is chosen, and not externally imposed [Kant, by Bowie] |
6694 | Always treat humanity as an end and never as a means only [Kant] |
3731 | Rational beings necessarily conceive their own existence as an end in itself [Kant] |
4345 | For Kant, even a person who lacks all sympathy for others still has a motive for benevolence [Kant, by Hursthouse] |
4251 | If we are required to give moral thought the highest priority, this gives morality no content [Williams,B on Kant] |
16004 | If Kant lives by self-administered laws, this is as feeble as self-administered punishments [Kierkegaard on Kant] |
3711 | Only a good will makes us worthy of happiness [Kant] |
3713 | The function of reason is to produce a good will [Kant] |
3729 | Our inclinations are not innately desirable; in fact most rational beings would like to be rid of them [Kant] |
4344 | Actions where people spread happiness because they enjoy it have no genuine moral worth [Kant] |
3732 | Rational beings have a right to share in the end of an action, not just be part of the means [Kant] |
7670 | Kant is the father of the notion of exploitation as an evil [Kant, by Berlin] |
7591 | Kant completed Grotius's project of a non-religious basis for natural law [Scruton on Kant] |
7673 | Retributive punishment is better than being sent to hospital for your crimes [Kant, by Berlin] |
11150 | It is the mark of an educated mind to be able to entertain an idea without accepting it [Aristotle] |
3037 | Aristotle said the educated were superior to the uneducated as the living are to the dead [Aristotle, by Diog. Laertius] |
3730 | Non-rational beings only have a relative value, as means rather than as ends [Kant] |
8660 | There are potential infinities (never running out), but actual infinity is incoherent [Aristotle, by Friend] |
12058 | Aristotle's matter can become any other kind of matter [Aristotle, by Wiggins] |
3721 | We judge God to be good by a priori standards of moral perfection [Kant] |
8046 | We can only know we should obey God if we already have moral standards for judging God [Kant, by MacIntyre] |
20714 | God is not proved by reason, but is a postulate of moral thinking [Kant, by Davies,B] |
22729 | The concepts of gods arose from observing the soul, and the cosmos [Aristotle, by Sext.Empiricus] |