A more serious consideration is the method of investigation. A working man, who is perhaps unintelligent outside his own work, and in many cases married to a woman who is superior in refinement, may possibly be able to arouse his wife's sexual emotions, and also able to ascertain what those emotions are, and be willing to answer questions truthfully on this point, to the best of his ability, but he is by no means a witness whose evidence is final. While, however, Campbell's facts may not be quite unquestionable, I am inclined to agree with his conclusion, and Mantegazza's, that there is a very great range of variation in this matter, and that there is no age at which the sexual impulse in women may not appear. A lady who has received the confidence of very many women tells me that she has never found a woman who was without sexual feeling. I should myself be inclined to say that it is extremely difficult to find a woman who is without the aptitude for sexual emotion, although a great variety of circumstances may hinder, temporarily or permanently, the development of this latent aptitude. In other words, while the latent sexual aptitude may always be present, the sexual impulse is liable to be defective and the aptitude to remain latent, with consequent deficiency of sexual emotion, and absence of sexual satisfaction. This is not only indicated by the considerable proportion of my cases in which there is only moderate or slight sexual feeling. I have ample evidence that in many cases the element of pain, which may almost be said to be normal in the establishment of the sexual function, is never merged, as it normally is, in pleasurable sensations on the full establishment of sexual relationships. Sometimes, no doubt, this may be due to dyspareunia. Sometimes there may be an absolute sexual anesthesia, whether of congenital or hysterical origin. I have been told of the case of a married lady who has never been able to obtain sexual pleasure, although she has had relations with several men, partly to try if she could obtain the experience, and partly to please them; the very fact that the motives for sexual relationships arose from no stronger impulse itself indicates a congenital defect on the psychic as well as on the physical side. But, as a rule, the sexual anesthesia involved is not absolute, but lies in a disinclination to the sexual act due to various causes, in a defect of strong sexual impulse, and an inaptitude for the sexual orgasm.