“The philosopher Didactylos has summed up an alternative hypothesis as "Things just happen. What the hell".”

This line, in the more grammatical form, "Sum up at night what thou hast done by day", is from George Herbert's The Temple, The Church Porch, line 451.
Misattributed

Kyuss interview http://www.youtube.com/watch?v=Bqai2XYiFyI, The Rivoli, Toronto (December 13, 1992)

I Want to be a Mathematician: An Automathography (1985)

Since "the answers of the special sciences" do not reach "the horizon of total reality", they are given "without having to speak at the same time of 'God and the world.'" (p. 96)
Source: Leisure, the Basis of Culture (1948), The Philosophical Act, p. 95

On his film Blow-Up, as quoted in Michelangelo Antonioni : The Complete Films (2004) edited by Seymour Chatman and Paul Duncan, p. 113
Context: The photographer in Blow-Up, who is not a philosopher, wants to see things closer up. But it so happens that, by enlarging too far, the object itself decomposes and disappears. Hence there's a moment in which we grasp reality, but then the moment passes. This was in part the meaning of Blow-Up.

Source: The Emergence Of Probability, 1975, Chapter 4, Evidence, p. 31.

Quoted in: Clint Brown (1998) Artist to Artist, p. 32

The Country Life.
Bartlett's Familiar Quotations, 10th ed. (1919)

Source: Systems Thinking: Creative Holism for Managers (2003), p. 4