The distinction between matter and form, of which I am here speaking, is true also in regard to conversation.  It is chiefly intelligence, judgment, wit, and vivacity that enable a man to converse; they give form to the conversation.  However, the matter of the conversation must soon come into notice—­in other words, that about which one can talk to the man, namely, his knowledge.  If this is very small, it will only be his possessing the above-named formal qualities in a quite exceptionally high degree that will make his conversation of any value, for his matter will be restricted to things concerning humanity and nature, which are known generally.  It is just the reverse if a man is wanting in these formal qualities, but has, on the other hand, knowledge of such a kind that it lends value to his conversation; this value, however, will then entirely rest on the matter of his conversation, for, according to the Spanish proverb, mas sabe el necio en su casa, que el sabio en la agena.

A thought only really lives until it has reached the boundary line of words; it then becomes petrified and dies immediately; yet it is as everlasting as the fossilised animals and plants of former ages.  Its existence, which is really momentary, may be compared to a crystal the instant it becomes crystallised.

As soon as a thought has found words it no longer exists in us or is serious in its deepest sense.

When it begins to exist for others it ceases to live in us; just as a child frees itself from its mother when it comes into existence.  The poet has also said: 

  “Ihr muesst mich nicht durch Widerspruch verwirren!
  Sobald man spricht, beginnt man schon zu irren.”

The pen is to thought what the stick is to walking, but one walks most easily without a stick, and thinks most perfectly when no pen is at hand.  It is only when a man begins to get old that he likes to make use of a stick and his pen.

A hypothesis that has once gained a position in the mind, or been born in it, leads a life resembling that of an organism, in so far as it receives from the outer world matter only that is advantageous and homogeneous to it; on the other hand, matter that is harmful and heterogeneous to it is either rejected, or if it must be received, cast off again entirely.

Abstract and indefinite terms should be employed in satire only as they are in algebra, in place of concrete and specified quantities.  Moreover, it should be used as sparingly as the dissecting knife on the body of a living man.  At the risk of forfeiting his life it is an unsafe experiment.

For a work to become immortal it must possess so many excellences that it will not be easy to find a man who understands and values them all; so that there will be in all ages men who recognise and appreciate some of these excellences; by this means the credit of the work will be retained throughout the long course of centuries and ever-changing interests, for, as it is appreciated first in this sense, then in that, the interest is never exhausted.