Click on the phrases to see them in context. The original texts by Immanuel Kant and David Hume are available from the Gutenberg Projet.

We should not be in this case affirming that these sensuous effects began to exist of themselves, because they are always determined by prior empirical conditions--by virtue of the empirical character, which is the phenomenon of the intelligible character--and are possible only as constituting a continuation of the series of natural causes.