You have chosen 'Theory of Science (4 vols)' by Bernard Bolzano, 'A Note on the entscheidungsproblem' by Alonzo Church and 'Constructibility and Mathematical Existence' by Charles Chihara
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 |