Again, if the condition of quality (in which are inclnded many im portant circumstances connected with both the temporary and per manent state of the brain, each of which is probably not less important than size) must be regarded as a constant source of inappreciable error in estimating the material condition of the organs, there is scarcely less fallibility in the other element of a phrenological observation, namely, the determination of the mental character of the individual examined. The actions of men are taken as the index to their phrenological state ; but (not to mention the cases in which men feign the possession of dispositions and opinions which are not their own) it is evident that in numerous instances, in which there is no intention to deceive,'the same actions proceed from different motives, and this phrenologists fully admit, for in many cases in which the size of certain parts of the brain does not agree with the apparent energy of the functions usually allotted to them, they refer the prominent actions of the individual under examination to the excess or defect of some other parts of the brain. But if in one case an apparent disagreement between the state of any faculty and of its presumed organ is thus easily capable of explanation by the condition of other faculties and organs, then in every case the state of all the other faculties must become an inappre ciable source of fallacy in endeavouring to estimate the condition of any one.
It is unfair to make use of these supplemental modes of determining characters in cases that are opposed to phrenology, and not to admit their influence in those which seem favourable to it. If the actions of a man are to be taken as the index of his mind—but if at the same time it is allowed that the same actions may result from different pro pensities, desires, and tastes, it is evident that it will be almost im possible to bring the evidence of facts to bear against phrenology, in which there must then be so many facilities of escape from conviction of error. If, to take an illustration from the writings of Sir G. Mackenzie, a young man in whom locality and inhabitiveness are very moderately developed is yet irresistibly impelled to go to sea, by a mechanical genius, and by attachment to the mechanism of a ship, conjoined with perseverance, courage, love of approbation, and ideality, there can surely be no certainty that any one propensity is proportioned to the condition of a single organ rather than to the combined condition of several others.
When we point out these sources of fallacy in every phrenological 'observation that has been made, and add to them the doubt which is cast upon it by the total absence of any anatomical peculiarity in the brain correspondent with the presumed separation of its organs, and by the failure of its application in the comparison of the psychical con dition of man and animals, sufficient has been done to show that a person exercises a justifiable and even a philosophical degree of caution in withholding his assent from phrenology as it at present stands. He may grant, as the writer does, that its theory is ingenious and pro bable ; that its plan of classifying the faculties of the mind is probably more natural than that of any other psychological system ; that the existence of many of the assumed faculties admits of little doubt; that a comparison of the heads of different nations and individuals renders it almost certain that the general divisions of the part of the human cerebrum are correct ; that in many cases, on balancing the evidence on each side, the result is on the whole favourable to the belief that the positions of several of the organs in each part of the brain have been nearly determined ; but without further and very extended inquiry, and that made with a just appreciation of the difficulties of attaining to facts, when so many of the elemeuts of the observations are inappreciable, and conducted by a disposition to doubt rather than to find confirmation of the doctrine assumed, he will hesitate to accept its theory further than as a direction to his inquiries, and will refuse to admit its applications in any important practice.