Knowledge is of no value unless you put it into practice.

One of the secrets of life is 

that all that is really worth the doing 

is what we do for others.

No other question has ever moved so profoundly the spirit of man; 

no other idea has so fruitfully stimulated his intellect; 

yet no other concept stands in greater need of clarification 

than that of the infinite.

The shepherd always tries to persuade the sheep that their interests and his own are the same.

They who dream by day 

are cognisant of many things 

which escape those 

who dream only by night.

Ideas govern the world, 

or throw it into chaos.

Ultimately, 

we actually all belong to only one tribe, 

to Earthlings.

The greater the obstacle, 

the more glory in overcoming it.

Heredity provides for the modification of its own machinery.

Believe that life is worth living 

and your belief will help create the fact.

Nothing is more beautiful than the loveliness of the woods before sunrise.

One's life has value 

so long as one attributes value to the life of others, 

by means of love, friendship, indignation and compassion.

A wise man gets more use from his enemies 

than a fool from his friends.

We must be willing to let go of the life we have planned, 

so as to have the life that is waiting for us.

The man of science, 

like the man of letters, 

is too apt to view mankind 

only in the abstract, 

selecting in his consideration 

only a single side 

of our complex and many-sided being.

The individual has always had to struggle 

to keep from being overwhelmed by the tribe. 

If you try it, 

you will be lonely often, 

and sometimes frightened. 

But no price is too high to pay 

for the privilege of owning yourself.