A pretty cool concept well executed.
Even if some of my guesses were somewhat random, I'm still surprised I managed to find everyone witheout ever cheating, wich is a testament about how well designed this game is given how that task seems daunting at first.
Special mention to the immaculate sound design too : the contrast between the noisy past and the silencious present is definitely one of the most memorable aspect of the game for me.

Then again, if this is clearly a very well-made game, I don't see the masterpiece everyone else claim it is. Maybe my expectations were too high, but I found the story to be fine, but nothing else, although the way said story is told doesn't help. I also expected more "memorable moments" : the kind of scenes that stay with you even years after playing the game. While I think our first vision of The Doom and the monkey paw fit that category (if you know you know), I guess it's still not enough for me.
Plus a few answers are pretty bullshit, let's be real.

Still, if someone asked me for a game that will make them feel smart, there's no doubt I'll recommend them that one.