r, with the _Opus Majus_ that Bacon's real activity begins. It
has been called by Whewell at once the Encyclopaedia and the Organum of the
13th century.

Part I. (pp. 1-22), which is sometimes designated _De Utililate
Scientiarum_, treats of the four _offendicula_, or causes of error. These
are, authority, custom, the opinion of the unskilled many, and the
concealment of real ignorance with pretence of knowledge. The last error is
the most dangerous, and is, in a sense, the cause of all the others. The
_offendicula_ have sometimes been looked upon as an anticipation of Francis
Bacon's _Idola_, but the two classifications have little in common. In the
summary of this part, contained in the _Opus Tertium_, Bacon shows very
clearly his perception of the unity of science and the necessity of
encyclopaedic treatment.

Part II. (pp. 23-43) treats of the relation between philosophy and
theology. All true wisdom is contained in the Scriptures, at least
implicitly; and the true end of philosophy is to rise from the imperfect
knowledge of created things to a knowledge of the Creator. Ancient
philosophers, who had not the Scriptures, received direct illumination from
God, and only thus can the brilliant results attained by them be accounted
for.

Part III. (pp. 44-57) treats of the utility of grammar, and the necessity
of a true linguistic science for the adequate comprehension either of the
Scriptures or of books on philosophy. [v.03 p.0155] The necessity of
accurate acquaintance with any foreign language and of obtaining good
texts, is a subject Bacon is never weary of descanting upon. A translator
should know thoroughly the language he is translating from, the language
into which he is translating, and the subject of which the book treats.

Part IV. (pp. 57-255) contains an elaborate treatise on mathematics, "the
alphabet of philosophy," maintaining that all the sciences rest ultimately
on mathematics, and progress only when their facts can be subsumed under
mathematical principles. This fruitful thought he illustrates by showing
how geometry is applied to the action of natural bodies, and demonstrating
by geometrical figures certain laws of physical forces. He also shows how
his method may be used to determine some curious and long-discussed
problems, such as the light of the stars, the ebb and flow of the tide, the
motion of the balance. He then proceeds to adduce elaborate and sometimes
slightly grotesque reasons tending