I was unable to go to this first conference because of my age and my health. ...Since that time I have made several journeys abroad, though none so long as that to Pugwash. I fight shy of longer journeys partly because I fear if I go to one country people in other countries who have pressed me to go there will be affronted. The only way around this, for one who is not an official personage, is to renounce distant travels.
Source: The Autobiography of Bertrand Russell, v.3 chap. 2
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