In spite of all that has been written about the concept of income, particularly by German authors, the meaning or scope of this concept still remains rather vague. This is no doubt because no one has ever really spelled out to himself the purpose the definition of this concept is actually supposed to serve. In itself it is, of course, primarily a question of terminology, and the answer given should not necessarily always be the same. On the contrary, it is quite likely that the concept of income in civil law, e.g. as used in bookkeeping, cannot be exactly the same as income in fiscal law; at least as far as is known, no successful attempt has ever been made to base a person’s taxation simply on his accounts, however correctly they may have been kept.