Emmanuel Ordóñez Angulo in The Point:
This summer was my longest stay back home, in Mexico City, in my life as a philosophy student abroad. Because of course I failed to meet my goal of finishing coursework before the holiday, I went back to the studio space I used to rent for writing in Colonia Juárez, near the city centre. By “studio space” I mean the one unusable corner of an apartment in an early twentieth-century building that, the landlord claims, used to house the British diplomatic corps prior to the Mexican revolution, and that now brims with wild flora and peeling green walls.
It was there that the earthquake found me.
The essay I was grappling with deals with the old question whether the things we perceive—the things that we see and touch—have a reality that is independent of us. The relevant discussion starts with Immanuel Kant’s argument against Descartes’ skepticism about the empirical world.
While Descartes aimed to show that the only thing I can be certain of is my own existence, Kant argued that in order for that to be possible I need to in fact be aware of the world around me as actually existing independent of me. This is because, if I am aware of my existence as flowing in time, as I am, then there must be something fixed by reference to which I can be aware that I am not fixed but flowing. Precisely because Descartes is right that I can be certain that I exist, says Kant, I must be certain that a world distinct from me exists as well.
This argument is liable to numerous objections. A famous one, raised by contemporary philosopher Barry Stroud, is that Kant reasons illegitimately from a premise about subjective experience to a conclusion about the existence of objective reality. The problem is that one field of inquiry concerns how we experience and know the world, i.e. what our conceptual framework is like, while the other concerns what actually exists. According to Stroud, the most Kant’s premise can prove is that we experience the external world as existing.
More here.