Assumes past him was brave enough to take the mission, thinks that’s super dumb because there were definitely better candidates but accepts it.
“Well I guess that’s who I am. The smartest idiot to be brave enough to be shot into space.” Proceeds to wear that character as a mask to cover the fear and petty (justifiable) anger over his situation.
Post coma Grace is alarmingly blasé about risking his life and frequently jokes sarcastically about dying. He rushes through his work and makes many cavalier mistakes. He finds it quite easy to shrug off Rocky’s jabs at his work and readily admits when he’s wrong and Rocky is right.
This person is not the Ryland Grace from Earth. That Grace checked and double checked his work in the face of a race against the clock, he was petty and snarky every single time literally anyone even suggested he was wrong and he valued his life enough that the end of the world wasn’t enough to get him to risk it. He was also extremely uncomfortable about the original crew making light about their deaths.
Has an instinctual feeling that the situation he’s in isn’t right beyond the obvious. He can’t reconcile the idea that he would be brave enough to volunteer for the mission because in his gut he knows that he wasn’t and still isn’t. That’s why he said dumb when Rocky asked for the translation for brave when book Grace accepted that description. In the face of this he assumes that rather than something making him brave enough to volunteer, he was actually just caring and reckless enough to do it for his kids and the rest of humanity.
So this is the mask he must wear to overcome his fear, deep care for others with a dash of recklessness. This isn’t near as effective of a mask against fear, if it was enough he would have volunteered in the first place because that actually is who he is. So he has to try to move through the fear anyway, this winds up with him just trying to keep moving at a fast enough pace that the fear can’t catch him.
In the movie, Earth Grace and post coma Grace remain fairly consistent because they reduced the impact of his amnesia, which left him with an instinctual understanding of who he was as a person.
In the book, Earth Grace and post coma Grace have significant differences in how they respond to things due to the extreme levels of amnesia leaving him without even an instinctual understanding of himself, like for Christ sake he was genuinely worried he might be a pedophile for a second.
Yes book Grace was absolutely more bitchy and less awkward but there isn’t all that much difference in how they responded to the mission and stepped up to the plate once push came to shove. Movie Grace just wallowed more because he didn’t have the bravery mask to hide behind, and Book Grace messed around and wasted time making stupid mistakes, like leaving everything out knowing he was about to go into micro gravity, because he thought he was the scientist equivalent of Han Solo or something.
