Having shown that no part of matter is ever entirely without "form," Bruno leaves aside for the present the question whether all form (Spirit) is equally accompanied by matter. The form or world-soul is not more than one, for all numerical multiplication depends on matter. It is in itself unchanging; only the objects vary, the different portions of matter into which it enters: and although in the object it is the spirit or form which causes the part to differ from the whole, yet _it_ does not differ in the part or in the whole. There are differences of aspect only, according as it is regarded as (_a_) subsisting in itself, or as (_b_) the actuality and perfection of some object, or as (_c_) referred to different objects with different dispositions.[265] That is, Spirit in itself,--the universal Spirit,--the Spirit or Soul of a particular animate being, the Spirits or Souls of a number of different beings (a system of beings), these are all the same thing looked at from different points of view. It is the same unique Spirit which determines the life of the human individual, the development of the human race as a whole, and the persistence of the world; the soul of Caesar and the spirit of humanity are one with the soul of the universe. The relation of spirit to matter in Bruno's philosophy is more difficult to understand. Spirit is said to be neither external to nor mixed with matter, nor inherent in it, but "inexistent," _i.e._ associated with or present to it. Moreover it is defined and determined by matter, because having in itself power to realise particular things of innumerable kinds, it "contracts" or limits itself to realise a given individual; and on the other side the potency of matter, which is indeterminate, and capable of any form whatsoever, is "determined" to one particular kind; so that the one is cause of the definition and determination of the other. Thus particular bodies are modes (determinations) of spirit and also of matter. As the universal form, spirit is all-present throughout the universe, not however materially or in extension, but spiritually, _i.e._ intensively. Bruno's favourite illustration is that of a voice or utterance--"imagine a voice which is wholly in the whole of a room, and in every part of it; everywhere it is heard wholly, as these words which I speak are understood wholly by all, and would be even if there were a thousand present; and if my voice could reach to all the world, it would be all in all."[266] So the soul is individual, not as a point is, but, analogously to a voice, or utterance, filling the universe. It is clear from these passages that the finite soul has no more reality in this phase of Bruno's pantheism than in Spinoza's; not only is the world-soul one as _unique_, but it is also one as indivisible--there are no parts of it: it is wholly in each of the parts of the universe--in each of its realisations. The finite individual, as this particular soul in this particular body, is