And Allah has created you and then He will cause you to die, and of you there are some who are sent back to senility, so that they know nothing after having known (much). Truly! Allah is All-Knowing, All-Powerful.-Surah An-Nahl, Verse 70
The movie and the book has made me realise this: We derive so much meaning from-, place so much pride in-, and based a big part of our identities on: our work, our intellect, our strength, our beauty, our youth, our power and our wealth. But all these are temporary. How would we cope if these things are taken away from us?
In Alice's case, her sense of self was eaten away by the Alzheimer's Disease. For us, it could be old age, or an accident, a recession, an illness, a civil war or any other plot twists that life has in store. Point is, the rug can be pulled out from under us at any moment. A sobering thought which can really cut our ego down to size.