This method may be summed up in a single word as =observation=. All scientific description, all description that reflects a disinterested and impersonal search for fact, is got by way of observation. And observation implies three things: a certain attitude towards phenomena, a vivid experience of the particular phenomenon which is the object of observation, and an adequate report of this experience in words. The relation of these three things will be clear if we write a formula for observation, thus: psychological (vivid experience → full report). The adjective outside the bracket shows that we take up a psychological attitude to the world; in other words, that the world which we are exploring is (to use our catch-phrase again) the world with _man left in_. The adjective applies to the whole contents of the bracket; the experience which we are to have is mental experience, and our account of it is to be couched in psychological language. We are, then, ready for the experience; it comes, and we give it our best attention; we then express it in words; and we try to express it fully and adequately, in the words that it itself points to and requires. When the account has been written down, and so made available for other students, we have completed a psychological observation. When a number of such observations have been taken, we have the materials for a scientific description. _Observation is by no means easy_; “there is not one person in a hundred,” said Huxley, “who can describe the commonest occurrence with even an approach to accuracy.” The reasons are partly of a technical nature; the use of scientific method is a bit of skilled labour, and skilled labour presupposes training; at first we are likely to be careless and clumsy; we do not see the need of scrupulous care, just because we do not know exactly what it is that we are doing. The great reason lies, however, in that difference between science and common sense to which we have already adverted; common sense interprets, and science describes. Malobservation is due, in the great majority of cases, to the ingrained tendency of the onlooker to interpret, to explain, what he observes. How many educated men and women to-day believe that the full moon dissipates the clouds? and how many more believe that changes of the moon coincide in some way with changes of the weather?