The Aristotelian ideas, of which there are many in the "Microcosm," are probably not derived from a study of Aristotle's works, but from secondary sources. This we may safely infer from the way in which he uses or interprets them. An Aristotelian definition is a highly technical proposition in which every word counts, and requires a definition in turn to be understood. In the Aristotelian context the reader sees the methodical derivation of the concept; and the several technical terms making up the definition are made clear by illustrative examples. Aside from the context the proposition is obscure even in the original Greek. Now conceive an Arabic translation of an Aristotelian definition taken out of its context, and you do not wonder that it is misunderstood; particularly when the interpreter's point of view is taken from a school of thought at variance with that of Aristotle. This is exactly what happens to Ibn Zaddik. He quotes approvingly Aristotle's definition of the soul, and proceeds to interpret it in a manner not intended by the author of the "De Anima."[167] If he had read the context he could not have misunderstood the definition as he did. Unlike his predecessors, Ibn Zaddik did not confine himself to a special topic in philosophy or to the metaphysical aspects of Judaism. Isaac Israeli and Gabirol discuss special questions in Physics and Metaphysics without bringing them into relation with Judaism or the text of the Bible. Saadia takes cognizance of philosophical doctrine solely with a view to establishing and rationalizing Jewish dogma, and only in so far as it may thus be utilized. Bahya and Abraham bar Hiyya confine their philosophical outlook within still narrower limits, having Jewish ethics as their primary concern. All of the latter make a feature of Biblical interpretation, which lends to their work the Jewish stamp and to their style the element of homeliness and variety. To this they owe in a measure their popularity, which, however, cannot be said for Abraham bar Hiyya, whose "Hegyon ha-Nefesh" was not printed until the second half of last century. The "Microcosm" of Ibn Zaddik is the first compendium of science, philosophy and theology in Jewish literature. And yet it is a small book; for Ibn Zaddik does not enter into lengthy discussions, nor does he adorn his style with rhetorical flourishes or copious quotations from Bible and Talmud. The "Olam Katon" is clearly meant for beginners, who require a summary and compendious view of so much of physics, psychology, metaphysics and ethics as will give them an idea of the position of man in the world, and his duties, theoretical and practical, in this life, that he may fulfil his destiny for which he was created. It is very possible that Ibn Zaddik modelled his work on the Encyclopædia of the Brethren of Purity, leaving out all that he regarded as unessential or objectional and abridging the rest.