Compliments from the Philips Research Laboratory in Brussels:

• Dominique de Walefffe
• Pascal Gribomont
• André Rifaut
• Dominique Roelants

betreft: Important Request

Waarde Edsger,

hierbij een Brabantsch Gebakkraam van een welbekend kunstenaar. Ik hoop nog vele EWD's te zullen lezen en wens je nog vele vruchtbare jaren toe! Geef ook Ria onze hartelijke groeten.

Tot weerziens

Anne Kaldewaij

Dear prof. Dijkstra,

I am spending my winter-holiday in a small cabin in the middle of Lapland. Days go in skiing, but in the evenings I have ample time to the latest EWD's (992–1000) which arrived already in late February. My normal working days are nowadays so full of all sorts off "duties", that interesting things have to be postponed to holidays. Anyway, I am enjoying EWD-series very much and eagerly waiting for the next thousand.

Yours ever,

Heikki Saikkonen

In his technical report (MR 34) of October 1961, Dijkstra explained why he viewed a good programming language to be one of a small number of very general concepts. To clarify, he used an analogy between mathematics and programming, an analogy which in later years would be scrutinized in several ways by his contemporaries. (See e.g. MacKenzie's 2004 book Mechanizing Proof: Computing, Risk, and Trust.)

In the late summer of 1981, Dijkstra gave several talks in Scotland and Newcastle. Here is an overview of his trip:

+ The Marine Hotel in North Berwick. The host was Mr. Hannah of Burroughs. The audience consisted of 10 men from various Burroughs plants in Europe. Dijkstra lectured for five successive days, between 6 and 7 hours per day. The "standard surprise" from the audience was that the universal quantification over the empty set yields true.