• "Even if we had a Grand Unified Theory Of Everything we still wouldn't know why the universe bothers to exist." -- Stephen Hawking

• "I know that love is better hate but I can't tell you why." -- Bertrand Russell

• "Why do you not commit suicide?" -- Viktor Frankl

Other important ones:

• Why Laugh.

• Matthew Parris' "Why do Western politicians take risks", exemplified by his own extraordinary risk-taking looking for anonymous homosexual encounters on Clapham Common while still an MP.

There is a fuller summary of three of these in Why As Jazz Gig.

Not all why questions are a good idea however. Here are some to avoid:

• the Stupid Why Question
• the Unanswerable Why Question
• the Disgusting Why Question

with

• the Demanding Why Question

requiring at least a great deal of patience from the questioner to become a good idea.