The things you think about determine the quality of your mind.

Your mind will take on the character of your most frequent thoughts: souls are dyed by thoughts.

Nothing is so productive of greatness of mind as the ability to examine systematically and truthfully each thing we encounter in life, and to see these things in such a way as to comprehend the nature of the Cosmos.

A human being has close kinship with the whole human race -- not a bond of blood or seed, but a community of mind. And you have forgotten this too, that every man's mind is a god and has flowed from that source; that nothing is our own property, but even our child, our body, our very soul have come from that source; that all is as thinking makes it so; that each of us lives only the present moment, and the present moment is all we lose.

..a man cannot lose a thing if he has it not.

Things of themselves cannot touch the soul at all. They have no entry to the soul, and cannot turn or move it. The soul alone turns and moves itself, making all externals presented to it cohere with the judgements it thinks worthy of itself.

Nothing has such power to broaden the mind as the ability to investigate systematically and truly all that comes under thy observation in life.

Purge your mind of all aimless and idle thoughts, especially those that pry into the affairs of others or wish them ill.

Tranquility is nothing else than the good ordering of the mind.