Psychological Investigations 243
"Another general experience is that the power of seeing vivid images in the mind's eye has little connection with high or low ability, or any other obvious characteristic, so that at present I am often puzzled to guess from my general knowledge of a friend, whether he will prove on inquiry to have the faculty or not. I have instances in which the highest ability is accompanied by a large measure of this gift, and others in which the faculty appears to be almost wholly absent. It is not possessed by all artists, nor by all mathematicians, nor by all mechanics, nor by all men of science. It is certainly -hot possessed by all metaphysicians, who are too apt to put forward generalisations, based solely on the experiences of their own special
way of thinking, in total disregard of the fact that the mental operations of other men may be conducted in very different ways to their own." (Nature, p. 252.)
"Although philosophers may have written to show the impossibility of our discovering what goes on in the minds of others, I maintain an opposite opinion. I do not see why the report of a person on his own mind should not be as intelligible and trustworthy as that of a traveller upon a new country, whose landscapes and inhabitants are of a different type to any which we ourselves have seen. It appears to me that inquiry into the mental constitution of other people is a most fertile field for exploration, especially as there is much in the facts adduced here, as well as elsewhere, to show that original differences in mental constitution are
permanent, being little modified by the accidents of education', and that they are strongly hereditary." (Nature, p. 256.)
Our Plates (XXI and XXII) give specimens of number forms. The Galtoniana contains many more and further slides of a certain number of coloured ones which do not appear in the published papers.
The next paper we reach was given as a Friday evening discourse at the Royal Institution, May 13, 1881'. It is entitled : "The Visions of Sane Persons." The object of this lecture was to show the unexpected prevalency of a visionary tendency among persons who form a part of ordinary society. Visions, illusions, hallucinations are stages of the same mental phenomenon, and may grade in intensity up to the star of Napoleon I or the daimon of Socrates and ultimately link up with a touch of madness.
Galton commences his lecture with referring in succession to
(a) Number Forms. "Strange visions for such they must be called, extremely vivid in some cases, but almost incredible to the great majority of mankind," who are inclined to set them down as fantastic nonsense.
(b) The Association of Colour with Sound. The persistence of colour association with sound is fully as remarkable as that of Number Forms with numbers; generally it is concerned with the vowel sounds, and it is not a mere general colour, but a very distinct tint of that colour, which is associated with the given sound. The association is permanent, but very arbitrary, no two persons agreeing in their distribution of tints to sounds.
(c) Association of Words with visualised Pictures. Sometimes this curious fantasy occurs in a vague fleeting way, but occasionally the pictures are strangely vivid and permanent. Thus in Mrs Haweis' mind the interrogation
1 This sentence since visualisation is part of the mental constitution does not seem wholly in accord with Galton's view that it should be possible by education to raise the intensity of that faculty in the general population so that the present grade at the upper suboctile should
represent that of the lower quartile of the new population.
2 Published also in the Fortnightly Review, June, 1881; Proceedings, Royal Institution, Vol. ix, pp. 644-55, 1882.