12 ideas
| 21962 | Metaphysics is the roots of the tree of science [Descartes] |
| Full Idea: The whole of philosophy is like a tree. The roots are metaphysics, the trunk is physics, and the branches emerging from the trunk are all the other sciences. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647]), quoted by A.W. Moore - The Evolution of Modern Metaphysics 01.2 | |
| A reaction: If Descartes had not believed this he would not have bothered with metaphysics, and philosophy might have been dead by 1650. |
| 2661 | Dialectic is speech cast in the form of logical argument [Cicero] |
| Full Idea: Dialectic is speech cast in the form of logical argument. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], I.viii.32) |
| 3659 | I know the truth that God exists and is the author of truth [Descartes] |
| Full Idea: I have very clearly deduced the following truths, that there is a God who is the author of all that is in the world, and who is the source of all truth. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.180) |
| 2673 | There cannot be more than one truth [Cicero] |
| Full Idea: There cannot be more than one truth. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xlviii.147) |
| 2669 | Dialectic assumes that all statements are either true or false, but self-referential paradoxes are a big problem [Cicero] |
| Full Idea: It is a fundamental principle of dialectic that every statement is either true or false. So is this a true proposition or a false one: "If you say that you are lying and say it truly, you lie"? | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xxix.95) |
| 3657 | Understanding, not the senses, gives certainty [Descartes] |
| Full Idea: Certainty is not in the sense but in the understanding alone, when it has evident perceptions. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.177) |
| 2664 | If we have complete healthy senses, what more could the gods give us? [Cicero] |
| Full Idea: If human nature were interrogated by some god as to whether it was content with its own senses in a sound and undamaged state or demanded something better, I cannot see what more it could ask for. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.vii.19) |
| 2665 | How can there be a memory of what is false? [Cicero] |
| Full Idea: How can there possibly be a memory of what is false? | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.vii.22) |
| 20800 | Every true presentation can have a false one of the same quality [Cicero] |
| Full Idea: [The sceptical Academics say] what is false cannot be perceived, but every true presentation is such that there can be a false presentation of the same quality. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.40) | |
| A reaction: It was the stoics who focused the discussion on 'presentations'. This claim is purely theoretical; no one has ever experienced a false presentation of talking to a family member that was as vivid as the real thing. |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
| Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice. | |
| From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where? |
| 2672 | Virtues must be very detached, to avoid being motivated by pleasure [Cicero] |
| Full Idea: None of the virtues can exist unless they are disinterested, for virtue driven to duty by pleasure as a sort of pay is not virtue at all but a deceptive sham and pretence of virtue. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xlvi.140) |
| 3660 | Atheism arises from empiricism, because God is intangible [Descartes] |
| Full Idea: The existence of God has been doubted by some, because they attributed too much to the perceptions of the senses, and God can be neither seen nor touched. | |
| From: René Descartes (Preface to 'Principles of Philosophy' [1647], p.180) |