Popper speaks about three worlds. World1 being the real world ’out there’ whose existence has to be taken on faith, and whose acceptance is widely known as the ’realist’ stand as oppossed to the ’idealist’. It is in this world we are, whether we want it or not, and on the arena of which ultimately all tests of falsifications are being performed. This world1 interacts with our world2, namely of our inner lives, the lives of subjectivity and non-reproducible qualia. World3 is the creation of world2, it is the world of narratives, theories, and all other imaginative products of the human mind. While world2 cannot interact directly with world1, it can do so, mysteriously through the mediation of world3. The remarkable thing is that world3 although a production of our minds, yet is ultimately independant of it.
Unended Quest, popper
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