You have chosen 'A Problem about Substitutional Quantification?st1=Saul A. Kripke' by , 'Queries to the 'Opticks'' by Isaac Newton and 'Reflections on Knowledge, Truth and Ideas' by Gottfried Leibniz
start again | choose another area for these texts | all the ideas for this combination of texts| All the ideas for Natural Theory, or select a subheading: |
| A. | Speculations on Nature | |
| B. | Natural Kinds | |
| C. | Causation | |
| D. | Laws of Nature |