The reason eval is there is because when you need it, when you really need it, there are no substitutes. There's only so much you can do with creative method dispatching, after all, and at some point you need to execute arbitrary code.

what i want you to do is to now imagine somebody whose body you would like to have 00:28:23 as your own either for a few minutes or maybe long term i'm not going to ask you why you want that body i don't want to get that deep into your psyche and that might be very personal um 00:28:35 but i'll tell you whose body i'd like to have and for how long just to give you a warm-up feel for this i really would like to have usain bolt's body of a few years ago for 9.6 seconds 00:28:47 because i would love to know what it feels like to run 100 meters that fast now when i form that does i think it's a coherent desire how do i why do i think that because i really do desire it i would love it i'd pay a lot of money to 00:28:59 do that um but what i don't want is to be usain bolt because usain bolt is already the same bolt and that doesn't do me any good um what i want is to be me 00:29:12 j with usain bolt's body so i can know what it feels like to run really really fast now i'm not claiming that this is a coherent desire i'm not claiming that it's 00:29:24 possible for me to remain jay and have usain bolt's body but i am claiming that i can desire it and if you are anything like me for some body or other you can desire to 00:29:36 have it for some time or other if you can form that desire then you in deep in your gut don't believe that you are your body you believe that you have a body and that 00:29:48 you might have a different body just like you might have a different hat or a different cat and if you believe that then you really do believe that whatever you are you are not your body 00:30:01 now you might think well that's obviously true i've never thought i was my body um but maybe on my mind i don't think you really believe that either and i want to do the same thought 00:30:13 experiment to convince you of that now i want you to think about somebody's mind that you'd really like to have maybe not for a long time maybe only for a few minutes um i'll tell you mine again i'm really 00:30:25 big and divulging you know hyper sharing over sharing personal secrets um i would really love to have stephen hawking's mind when he was still alive of course not now um and i'd like to have it only for about five or ten 00:30:36 minutes because what i would really like is to be able to really understand quantum gravity and i can't really understand it but if i had stephen hawking's mind for a few minutes then i could understand it now i obviously 00:30:48 don't want to be stephen hawking for one thing he's dead for another thing he was already stephen hawking and it didn't do me a damn bit of good what i want is to be me jay with his mind so that i can 00:31:00 use it to understand quantum gravity um i think that'd be really cool again i'm not claiming this is coherent i'm not claiming that it's possible but i am claiming that it's a 00:31:11 psychologically possible state to be in to crave somebody else's mind and if you like me can form that desire then you like me deep in your gut do not believe that you are your mind 00:31:25 you believe that you're something that has a mind just like you have a body um and that you possessed that mind and you could still be you with another mind and another body i mean just imagine having 00:31:37 the same bolts body in stephen hawking's mind that would be totally cool then i could understand quantum gravity while setting a new record for the 100 meter sprint um but that's not going to happen alas 00:31:50 um the moral of these experiments um takes us right back to chandragiri serpent i think the moral of these experiments is that deep down at an atavistic gut 00:32:02 level we believe that we are something that stands behind our minds and our bodies that thing is the self the thing that is not the mind in the body but possesses the mind in the body that's the thing 00:32:14 that sean decurity identifies as the serpent in the wall our arguments are going to be aimed at that not at our bodies not as our minds not as our personal identities they're 00:32:27 going to be aimed at that self that we really atavistically believe stands behind all of those that's the illusion that's the thing that causes us to be incompetent morally that causes us to be 00:32:41 confused about our own identities and to be confused about our role and our place in the world

$ nix-env -i firefox --substituters ssh://alice@avalon This works similar to the binary cache substituter that Nix usually uses, only using SSH instead of HTTP

substitute

When you ask Nix to install a package, it will first try to get it in pre-compiled form from a binary cache. By default, Nix will use the binary cache https://cache.nixos.org; it contains binaries for most packages in Nixpkgs. Only if no binary is available in the binary cache, Nix will build the package from source. So if nix-env -i subversion results in Nix building stuff from source, then either the package is not built for your platform by the Nixpkgs build servers, or your version of Nixpkgs is too old or too new.