It is certain that the domain of the indifferent states, if existent at all, is very scanty. Yet, however skilfully Bouillier may support his thesis, there is one irrefragable objection to be urged against it: the testimony of the consciousness, always doubtful, is here more so than elsewhere. What he proposes to us is, in fact, to _observe_ ourselves. From the moment when we begin to do this, we no longer have to deal with the natural consciousness, in its raw state, but with that somewhat artificial consciousness which is created by attention. We look, not with our eyes, but through a microscope; we amplify, we enlarge the phenomenon; and here the method of enlargement is not to be trusted. It causes certain subconscious states to cross the threshold of the consciousness; it makes them pass out of the penumbra into full light, and disposes us to believe that such is their normal condition. We know that some individuals, by fixing the attention firmly on some particular part of the body, can bring about in it a sensation of weight, of irritation, of arterial pulsation, etc. Do these modifications always exist, unperceived only so long as the attention is not directed to them? or does attention produce them by means of an increased vascular activity, increasing, but not creating? The latter supposition is the more probable. The hypochondriac who obstinately and patiently watches the details of his organic life feels within himself the motion of the vital mechanism which escapes most men. It would be easy to give other examples, proving that we must distinguish between consciousness pure and simple and internal observation, and that it is the less allowable to argue from one to the other, since in practice the problem is reduced to a difference of intensity. This question well deserves to be called, as it has been by J. Sully, “one of the _cruces_ of psychology.” Those who wish to take sides in it can only guide their decision by probabilities and preferences. I am inclined to favour the thesis of indifferent states. I find it difficult to admit that certain perceptions or representations, incessantly repeated, imply anything more than the fact of knowledge. The sight of my furniture, arranged in its usual order, causes me no appreciable degree of pleasure or displeasure; or if these exist as infinitesimal quantities, psychology, as Bain justly says, has no concern with them. Fouillée also points out that the feeling of indifference is not primary, but due to an effacement.[57] Footnote 57: Fouillée, _Psychologie des idées-forces_, i. 68.