Combining Texts

All the ideas for 'Letters to Samuel Clarke', 'Carnap and Logical Truth' and 'Frege's Theory of Numbers'

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25 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
The principle of sufficient reason is needed if we are to proceed from maths to physics [Leibniz]
There is always a reason why things are thus rather than otherwise [Leibniz]
No reason could limit the quantity of matter, so there is no limit [Leibniz]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / a. Set theory paradoxes
Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Parsons says counting is tagging as first, second, third..., and converting the last to a cardinal [Parsons,C, by Heck]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine]
7. Existence / C. Structure of Existence / 6. Fundamentals / c. Monads
All simply substances are in harmony, because they all represent the one universe [Leibniz]
8. Modes of Existence / A. Relations / 1. Nature of Relations
The ratio between two lines can't be a feature of one, and cannot be in both [Leibniz]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine]
10. Modality / A. Necessity / 6. Logical Necessity
Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine]
12. Knowledge Sources / A. A Priori Knowledge / 7. A Priori from Convention
Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / g. Atomism
Things are infinitely subdivisible and contain new worlds, which atoms would make impossible [Leibniz]
The only simple things are monads, with no parts or extension [Leibniz]
Atomism is irrational because it suggests that two atoms can be indistinguishable [Leibniz]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
Leibniz upheld conservations of momentum and energy [Leibniz, by Papineau]
27. Natural Reality / C. Space / 4. Substantival Space
The idea that the universe could be moved forward with no other change is just a fantasy [Leibniz]
27. Natural Reality / D. Time / 1. Nature of Time / b. Relative time
Space and time are purely relative [Leibniz]
27. Natural Reality / D. Time / 1. Nature of Time / i. Denying time
No time exists except instants, and instants are not even a part of time, so time does not exist [Leibniz]
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
If everything in the universe happened a year earlier, there would be no discernible difference [Leibniz]
28. God / A. Divine Nature / 5. God and Time
If time were absolute that would make God's existence dependent on it [Leibniz, by Bardon]
28. God / B. Proving God / 3. Proofs of Evidence / a. Cosmological Proof
The existence of God, and all metaphysics, follows from the Principle of Sufficient Reason [Leibniz]