Suppose you mean lossless compression
Right; with lossless compression then you're not going to lose anything. So cousin_it probably means lossy compression, like with jpgs and mp3s, smaller versions that are very similar to what you had before.
Well, initial mind uploading is going to be lossy because it will convert analog to digital.
That said, I don't know if even lossless compression of the whole input-output map is going to preserve everything. Let's say you have ten seconds left to live. Your input-output map over these ten seconds probably doesn't contain many interesting statements about consciousness, but that doesn't mean you're allowed to compress away consciousness...
And even on longer timescales, people don't seem to be very good at introspecting about consciousness, so all your belie...
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