12 August 1918.
          My dear Frank - I wish you to know exactly the reasons why I am anxious to be released as soon as possible. My reasons are not only, or even principally, that prison is disagreeable, though it is not, of course, a place of residence that one would choose for pleasure. My principal reason is that I have ideas for what I believe to be a really important piece of philosophical research, with which I am exceedingly anxious to make progress; but in spite of my utmost efforts I find it very hard to accomplish much while I remain here. During my first two months of imprisonment I did a great deal of work, as appeared from the MSS I sent out. But at the end of that time I had a series of bad headaches, which obliged me to be careful; & ever since I have found that I cannot work much without a return of the headaches, & that the work I can do is not very fruitful. Philosophical research is not like the work of a clerk or a housemaid: diligence alone is not enough to ensure success in it. One needs also that condition of mind & body in which new ideas come; & for that, diligence, though necessary, is not sufficient. I have been reluctantly forced to the conclusion that I shall not make much further progress with my work until I have had a holiday in country air & a chance to acquire more freshness than is to be found in a prison cell. I am sorry it is so, as I desire intensely to develop the ideas I have. Either Dr Whitehead or Professor Carr, to whom I spoke about them, will, I feel sure, confirm me in saying that these ideas are not unimportant, & that it is a pity they should not be worked out.
          You may remember that the chairman of the Quarter Sessions, in assigning me to the First Division, said that it would be a national misfortune if my philosophical work were interfered with. He was obviously humane & enlightened, but without experience of either prison or research. I feel convinced, from the way in which he spoke, that, if he knew the present state of affairs, he would favour my release. Apart from the question of physical fitness, I am seriously hampered by not having access to a library & by not being able to discuss philosophical questions except rarely & briefly. If you will consult any philosopher of your acquaintance, he will tell you that, although I ought to be able to work in prison, he himself, being of a peculiarly sensitive disposition, would be quite unable to do so. And the fact is that peculiarities of this kind are usual among those who have any capacity for original thought.

Your affec. brother
Bertrand Russell