Goethe started from the conviction that our senses as well as our intellect are gifts of nature, and that, if at any given moment they prove incapable through their collaboration of solving a riddle of nature, we must ask her to help us to develop this collaboration adequately. Thus there was no question for him of any restriction of sense-perception in order to bring the latter in line with the existing power of the intellect, but rather to learn to make an ever fuller use of the senses and to bring our intellect into line with what they tell. 'The senses do not deceive, but the judgment deceives', is one of his basic utterances concerning their respective roles in our quest for knowledge and understanding. As to the senses themselves, he was sure that 'the human being is adequately equipped for all true earthly requirements if he trusts his senses, and so develops them as to make them worthy of trust'. There is no contradiction in the statement that we have to trust our senses, and that we have to develop them to make them trustworthy. For, 'nature speaks upwards to the known senses of man, downwards to unknown senses of his'. Goethe's path was aimed at wakening faculties, both perceptual and conceptual, which lay dormant in himself. His experience showed him that 'every process in nature, rightly observed, wakens in us a new organ of cognition'. Right observation, in this respect, consisted in a form of contemplating nature which he called a 're-creating (creating in the wake) of an ever-creative nature' (Nachschaffen einer immer schaffenden Natur). * We should do Goethe an injustice if we measured the value of his scientific work by the amount of factual knowledge he contributed to one or other sphere of research. Although Goethe did bring many new things to light, as has been duly recognized in the scientific fields concerned, it cannot be gainsaid that other scientists in his own day, working along the usual lines, far exceeded his total of discoveries. Nor can it be denied that, as critics have pointed out, he occasionally went astray in reporting his observations. These things, however, do not determine the value or otherwise of his scientific labours. His work draws its significance not so much from the 'what', to use a Goethean expression, as from the 'how' of his observations, that is, from his way of investigating nature. Having once developed this method in the field of plant observation, Goethe was able, with its aid, to establish a new view of animal nature, to lay the basis for a new meteorology, and, by creating his theory of light and colour, to provide a model for a research in the field of physics, free from onlooker-restrictions.