ANTONIO ALIOTTA, La Misura in Psicologia Sperimentale. 559 More than enough has been said to prove that Prof. Bead's position unites interesting historical relations with strong originality. The freshness and vigour of his thought deserves every recognition, and if we have to pardon him, as he does Spinoza, for indulging a turn for style once in a hundred pages, the general care and dis- tinction and even charm with which he has expressed his thought make the reading of a really important work a very pleasant duty. It is the earnest desire of the present writer to commend it to the notice of any one who may as yet have neglected it. DAVID MOBRISON. La Misura in Psicologia Sperimentale. BY ANTONIO ALIOTTA, Professor of Philosophy in the Royal Liceo at Lucera. Firenze : Galletti e Cocci, 1905. Pp. 253 and 1 plate. THE text of this interesting work is Kant's assertion that psy chology can never be a true science owing to the impossibility of giving it a mathematical treatment. The book is divided into four parts (the last being extremely brief), which the author entitles psychophysics, psychochronometry, psychodynamics and psychostatistics, respectively. Of these the first and second are by far the best written, and will receive examination here. The first question which the author raises concerns the intensity of sensations. "We say that one red is more extensive than another just as we judge that one red is more intense than another. But are we justified in concluding, from this common- sense dictum, that a colour sensation considered as a psychical fact, can be more or less extensive? Certainly not. The state- ment that sensations have a certain character of extensity (spazialita) or intensity, must not be confused with the statement that sensations are more or less extensive or more or less intense. In speaking of the representation of space, all psychologists clearly distinguish between these two meanings, calling the one extensity (spazialita), the other extension (estensione) ; but owing to the lack of two appropriate words, some ambiguity generally exists as regards intensity. Nevertheless the two statements have admittedly a different value. It is one thing to say that a sen- sation is more or less intense : it is another to say that it has a certain character by virtue of which it can be placed in an in- tensive series. In the one we grant forthwith that sensation is a quantity susceptible of measurement : in the other we assert that a sensation is simply a qualitative entity, possessing a certain aspect, a certain colouring, whereby, when conjoined with other sensations of like kind, and elaborated with more highly developed processes by consciousness, it can afford a representation of the intensity of external phenomena" (pp. 49, 50). Whereupon Prof. Aliotta develops the following argument. " Sensations can have only that intensity with which they are ex-