You have chosen 'On Duties ('De Officiis')' by M. Tullius Cicero, 'Aristotle on Substance' by Mary Louise Gill and 'Principles of Nature and Grace based on Reason' 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 |