"Never let the future disturb you. You will meet it, if you have to, with the same weapons of reason which today arm you against the present." - Marcus Aurelius I think here 'reason' means the complete presence of awareness in a given moment. I have read some other of Marcus Aurelius' works and get a feeling that his usage of the word reason (which itself is a translation of some word in latin) is different from our usage of it (as of 2015). It probly means 'present moment awareness' or 'complete attention' or 'calm focus'.