63 ideas
| 1887 | You cannot divide anything into many parts, because after the first division you are no longer dividing the original [Sext.Empiricus] |
| 1848 | We are coerced into assent to a truth by reason's violence [Aquinas] |
| 1858 | The mind is compelled by necessary truths, but not by contingent truths [Aquinas] |
| 1885 | Proof moves from agreed premises to a non-evident inference [Sext.Empiricus] |
| 1852 | For the mind Good is one truth among many, and Truth is one good among many [Aquinas] |
| 13010 | In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine] |
| 9002 | Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine] |
| 13681 | Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider] |
| 12196 | A valid hypothetical syllogism is 'that which does not begin with a truth and end with a falsehood' [Sext.Empiricus] |
| 13829 | If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine] |
| 9003 | Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine] |
| 1902 | Since Socrates either died when he was alive (a contradiction) or died when he was dead (meaningless), he didn't die [Sext.Empiricus] |
| 9004 | If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine] |
| 9006 | Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine] |
| 9001 | Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine] |
| 1889 | If an argument has an absurd conclusion, we should not assent to the absurdity, but avoid the absurd argument [Sext.Empiricus] |
| 1871 | Whether honey is essentially sweet may be doubted, as it is a matter of judgement rather than appearance [Sext.Empiricus] |
| 9005 | Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine] |
| 1883 | How can the intellect know if sensation is reliable if it doesn't directly see external objects? [Sext.Empiricus] |
| 1890 | We distinguish ambiguities by seeing what is useful [Sext.Empiricus] |
| 1860 | Knowledge may be based on senses, but we needn't sense all our knowledge [Aquinas] |
| 1870 | The basis of scepticism is the claim that every proposition has an equal opposing proposition [Sext.Empiricus] |
| 1882 | The necks of doves appear different in colour depending on the angle of viewing [Sext.Empiricus] |
| 1872 | The same tower appears round from a distance, but square close at hand [Sext.Empiricus] |
| 1873 | If we press the side of an eyeball, objects appear a different shape [Sext.Empiricus] |
| 1881 | The same oar seems bent in water and straight when out of it [Sext.Empiricus] |
| 1874 | How can we judge between our impressions and those of other animals, when we ourselves are involved? [Sext.Empiricus] |
| 1876 | If we enjoy different things, presumably we receive different impressions [Sext.Empiricus] |
| 1877 | If we had no hearing or sight, we would assume no sound or sight exists, so there may be unsensed qualities [Sext.Empiricus] |
| 1880 | Some actions seem shameful when sober but not when drunk [Sext.Empiricus] |
| 1879 | Sickness is perfectly natural to the sick, so their natural perceptions should carry some weight [Sext.Empiricus] |
| 1878 | Water that seems lukewarm can seem very hot on inflamed skin [Sext.Empiricus] |
| 1910 | With us it is shameful for men to wear earrings, but among Syrians it is considered noble [Sext.Empiricus] |
| 1911 | Even if all known nations agree on a practice, there may be unknown nations which disagree [Sext.Empiricus] |
| 1886 | If you don't view every particular, you may miss the one which disproves your universal induction [Sext.Empiricus] |
| 1855 | If we saw something as totally and utterly good, we would be compelled to will it [Aquinas] |
| 1853 | Because the will moves by examining alternatives, it doesn't compel itself to will [Aquinas] |
| 1849 | Since will is a reasoning power, it can entertain opposites, so it is not compelled to embrace one of them [Aquinas] |
| 1862 | However habituated you are, given time to ponder you can go against a habit [Aquinas] |
| 1861 | The will is not compelled to move, even if pleasant things are set before it [Aquinas] |
| 1856 | Nothing can be willed except what is good, but good is very varied, and so choices are unpredictable [Aquinas] |
| 1854 | We must admit that when the will is not willing something, the first movement to will must come from outside the will [Aquinas] |
| 1884 | If we utter three steps of a logical argument, they never exist together [Sext.Empiricus] |
| 1857 | We don't have to will even perfect good, because we can choose not to think of it [Aquinas] |
| 1846 | The will can only want what it thinks is good [Aquinas] |
| 1847 | The will must aim at happiness, but can choose the means [Aquinas] |
| 1850 | Without free will not only is ethical action meaningless, but also planning, commanding, praising and blaming [Aquinas] |
| 1851 | Good applies to goals, just as truth applies to ideas in the mind [Aquinas] |
| 1894 | Some say that causes are physical, some say not [Sext.Empiricus] |
| 1896 | If there were no causes then everything would have been randomly produced by everything [Sext.Empiricus] |
| 1897 | Knowing an effect results from a cause means knowing that the cause belongs with the effect, which is circular [Sext.Empiricus] |
| 1898 | Cause can't exist before effect, or exist at the same time, so it doesn't exist [Sext.Empiricus] |
| 1895 | Causes are either equal to the effect, or they link equally with other causes, or they contribute slightly [Sext.Empiricus] |
| 1859 | Even a sufficient cause doesn't compel its effect, because interference could interrupt the process [Aquinas] |
| 1899 | Does the original self-mover push itself from behind, or pull itself from in front? [Sext.Empiricus] |
| 1900 | If time and place are infinitely divided, it becomes impossible for movement ever to begin [Sext.Empiricus] |
| 1901 | If all atoms, times and places are the same, everything should move with equal velocity [Sext.Empiricus] |
| 1903 | If motion and rest are abolished, so is time [Sext.Empiricus] |
| 1904 | Time must be unlimited, but past and present can't be non-existent, and can't be now, so time does not exist [Sext.Empiricus] |
| 1905 | How can time be divisible if we can't compare one length of time with another? [Sext.Empiricus] |
| 1891 | How can we agree on the concept of God, unless we agree on his substance or form or place? [Sext.Empiricus] |
| 1892 | The existence of God can't be self-evident or everyone would have agreed on it, so it needs demonstration [Sext.Empiricus] |
| 1893 | If God foresaw evil he would presumably prevent it, and if he only foresees some things, why those things? [Sext.Empiricus] |