Moral Philosophers Who Lose The Right To Pontificate.

Just how is it that 'moral' philosophers have the gall to lecture the rest of us on physical matters when they themselves display the sexual mores of an alley cat?
Bertrand Russell being one noteworthy case in point.

(I am perfectly aware of the imperfect behaviour of some noted Christians in the past - but only in cults do they justify their ignoble antics.)