809. As everything that we sense is therefore only a relationship between our own self or I and the thing we are sensing, our acknowledgment of the thing will, as we have said, be merely "relative", which in turn means that it will be merely the expression of one specific viewpoint. This viewpoint is in turn bound to be something different from other viewpoints. Every living being can therefore of necessity exist only with its own private viewpoint, since it is impossible to experience anything other than precisely the "relationship" between its I and the other objects in existence, whether they be its fellow beings or created objects. The old saying that "it's all in the eyes of the beholder" is therefore a truly scientific conclusion. The fact that the beings' views of things can exist only as "relative" means that they can exist only as views of, not the true nature of the things – there would be little sense in being able to sense only this, since this is synonymous with "X" – but, on the contrary, as the reactions of things, that is to say the meeting of the movements with the I. It is these reactions that constitute form, that constitute shape, that constitute "matter" and "spirit" and that thereby become what we have already begun to recognise as "life substances". And it is precisely on the basis of this relativity of the reactions that there exists the divine basic principle that is essential for all sensory perception, and which we will later get to know as the "principle of perspective". In reality this principle exists only as a certain, automatic arrangement of the placing of every detail in the sensory field in relation to the I.