No, my friend, I am not drunk. I have just been to the dentist, and need not return for another six months! Is it not the most beautiful thought? --Poirot

People who can be very good can be very bad too.

Where large sums of money are concerned, it is advisable to trust nobody.

It is the quietest and meekest people who are often capable of the most sudden and unexpected violences for the reason that when their control does snap, it goes entirely. (Hercule Poirot)

It is clear that the books owned the shop rather than the other way about. Everywhere they had run wild and taken possession of their habitat, breeding and multiplying, and clearly lacking any strong hand to keep them down.

Until one looks back on one's own past one fails to realise what an extraordinary view of the world a child has.

I have often had occasion to notice how, where a direct question would fail to elicit a response, a false assumption brings instant information in the form of a contradiction.