To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The Pölitz transcripts of Kant's lectures from the 1780s on rational theology contain a fascinating discussion of modality:
On this point rests the only possible ground of proof for my demonstration of God's existence, which was discussed in detail in an essay I published some years ago. Here it was shown that of all possible proofs, the one that affords us the most satisfaction is the argument that if we remove an original being, we at the same time remove the substratum of the possibility of all things. – But even this proof is not apodictically certain; for it cannot establish the objective necessity of an original being, but establishes only the subjective necessity of assuming [annehmen] such a being. But this proof can in no way be refuted, because it has its ground in the nature of human reason. For my reason makes it absolutely necessary for me to assume a being which is the ground of everything possible, because otherwise I would be unable to know what in general the possibility of something consists in [worin etwas möglich sey]. (Pölitz RT, Ak. 28:1034)
The “essay published some years ago” to which Kant here refers is his 1763 work The Only Possible Ground of Proof in Support of a Demonstration of the Existence of God (henceforth, OPG). While the exact interpretation of that work is controversial, it is clear that he there defends an interconnected set of claims about possibilities and their grounds:
(1) It is logically possible that p iff p does not entail a contradiction. This is the definition of logical possibility. (Ak. 2:77)
(2) Not all logical possibilities are real possibilities (Ak. 2:77, 85). Kant does not explicitly offer a developed theory of what real possibility is, but it is clear that real possibility is more “metaphysically robust” than mere logical possibility. He also lays down certain conditions on it. For instance,
(3) If it is really possible that p then some existing being grounds the fact that it is really possible that p (Ak. 2:78, 79). As with (2), Kant does not explicitly offer a developed theory of the relation between real possibilities and their grounds.
Lucy Allais’s anti-phenomenalist interpretation of transcendental idealism is incomplete in two ways. First of all, like some phenomenalists, she is committed to denying the coherence of claims of numerical identity of appearances and things in themselves. Secondly, she fails to explain adequately what grounds the actuality of appearances. This opens the door to a phenomenalist understanding of appearances.