This book gives a great overview of philosophy. I was a philosophy major in college and this book covers many of the ideas I learned at school. However, my only grievance is that it leaves some ideas out like Kantian ethics. But other than that I highly recommend this to people who like philosophy or want to learn more about it.

[I received a copy of this book through NetGalley.]

I’m not sure I can really call this ‘science fiction’—‘alternate history/contemporary world’, rather?— and for once I find ‘speculative fiction’ is actually more appropriate. ‘Yesterday’ is set in a 2015 world where people, due to a gene getting inhibited when they become adults, lose their short term memories. ‘Monos’ can only retain the previous days, while ‘Duos’ can retain two days... but nothing more. In order to function, people therefore have to keep writing in their diaries, and make a conscious effort to learn the important ‘facts’ that happened to them.

I found this premise quite interesting, especially when it came to setting a mystery in that world: how would an investigator go about their job, link clues together, if they can only rely on written facts and not on actual memories? Because they’re bound to forget to write some details that would then become important, only at the time they looked so trivial they didn’t think them so. This is DI Richardson’s conundrum, as the main investigator in Sophia Ayling’s suicide-or-murder case, since he knows he has to solve this very quickly, otherwise he may miss some important clues. Just like potential suspects will literally forget what a crafty interrogation session could have made them say. All of this, of course, while keeping in mind an important question: are diaries reliable?

The story revolves around four characters’ narratives and diaries: Claire Evans, a Mono ex-waitress who married a successful Duo writer, but struggles daily with her feelings of inadequacy compared to her husband’s ability to remember more; Mark Evans, whose career as a writer isn’t so satisfying anymore, just like his marriage, and who’s tempted to veer towards politics... and mistresses; Sophia Ayling, a woman with the rare ability to remember everything... including tiny little slights that built up into hatred and a deep desire for revenge; and Hans Richardson, the inspector determined to crack the case in one day, but who also harbours secrets of his own.

In itself, it was a fast-paced enough read (everything happens over 24 hours, after all), and one that kept my attention; the plot twists were easy enough for me to guess, yet at the same time I still wanted to see how the characters themselves, with their limited day to day memories, would go about making sense of everything that happened to them.

In the end, though, the memory limit proved to ask more questions than it provided answers, making the world building kind of... shaky? The society depicted here seems to have been built on the short term memory problem as if it had been here from the start. But while I can see how modern technology (paper diaries, then iDiaries—hello, parallel world Apple that I thought interesting in spite of being a little too obvious) would allow people to function, it makes one wonder how science and said technology developed in the first place: at some point, how was writing invented, if people couldn’t remember what they did two days ago, and couldn’t put it in written words? For me, it would’ve been more credible if the genetic shift had happened later in history—well, maybe it did, but the story doesn’t tell.

The ending, too, left me sceptical. I see what the author did there, but it felt too convoluted and resting on chance events (or perhaps, should I say, on a stroke of genius on one character’s part, but what led to it seemed too much like a convenient plot device?). Also, I would’ve expected the inspector character to make less blunders—either that, or other characters bearing on him for making them, because in the end there were no real consequences.

Conclusion: 2.5 stars. It is an entertaining first novel, I just wished the memory loss premise had been exploited better.