It ultimately boils down if you accept John Searle's Chinese room argument or not. (BTW his claim is not that conscious machines are not possible - we are such

It ultimately boils down if you accept John Searle's Chinese room argument or not. (BTW his claim is not that conscious machines are not possible - we are such machines, but they cannot be implemented as digital symbol manipulators; we first need to figure out what exactly makes the biological machines conscious).