Mathematics is the indispensable instrument of all physical research.
- by Marcellin Berthelot
It is a substitution cipher.
The cipher letters: k b e m z d j r q l f n a
The plaintext letters: m a t h e i c n d p l r o
f s y m
A few of the letters stand for two letters. For the words containing that letter, the decoded letter must be alternated.
For instance, letter k stands for both m and f. The first word, the fifth word, and the sixth word in the ciphertext all have k in it. So in the first word, k stands for m. In the fifth word, k stands for f, and in the sixth word, k stands for m.