Build a system that even a fool can use, and only a fool will want to use it.

Do not do unto others as you expect they should do unto you. Their tastes may not be the same.

Make it compulsory for a doctor using a brass plate to have inscribed on it, in addition to the letters indicating his qualifications, the words 'Remember that I too am mortal'.

The golden rule is that there are no golden rules.

[...] any fool can make a discovery. Every baby has to discover more in the first years of its life than Roger Bacon ever discovered in his laboratory.

The more I see of the moneyed classes, the more I understand the guillotine.

Most of my recent plays were written in the railway train between Hatfield and Kings Cross. I write anywhere, on the top of omnibuses or wherever I may be; it is all the same to me.