You have chosen 'Letter to Shumacher' by Carl Friedrich Gauss, 'What is an Idea?' by Gottfried Leibniz and 'On the Foundations of Logic and Arithmetic' by David Hilbert
start again | choose another area for these texts | all the ideas for this combination of texts| All the ideas for Modality, or select a subheading: |
| A. | Necessity | |
| B. | Possibility | |
| C. | Sources of Modality | |
| D. | Knowledge of Modality | |
| E. | Possible worlds |