97

Logic 97 On Observation of our own Creations

them is unsatisfactory.

13thly The chief source of logical truth though never recognised by logicians always has been amd must be the same as the source of mathematical truth.
This was well shown in a little book entitled 'Logisake Studien' by the historian of materialism Friedrich Albert Lange published 1877 having been unfortunately left unfinished at the author's death in 1875.
I have found few books on logic so instructive.
I do not ,ean that the reader will find Lange's view exactly reproduced in this work by any means upon a single topic.
But it has influenced me considerably and I can recommend it as one of the very few works on logic that I have found too short.

What then is the source of mathematical truth?
For that has been one of the most vexed of questions.
I intend to devote an early chapter of this book to it.
I will merely state here that my conclusion agrees substantially with Lange's that mathematical truth is derived