Practical success in life depends more upon physical health than is generally imagined. The capacity for continous working in any calling must necessarily depend on a great measure upon this; and hence the necessity for attending to health, even as a means of intellectual labour. A healthy breathing apparatus is as indespensable to the succesful personn as a well-cultured intellect. Because labour conquers all things.
We must not only strike the iron while it is hot, but strike it till it is made hot.
All these are quotes from the amazing Samuel Smiles.