Teacher of Alexander the Great, writer of the Nicomachean Ethics.
'Nothing exists except atoms and empty space; everything else is opinion'
This philosopher believed that things consisted of an infinite number of small particles called atoms (form the greek word atomo which means individual). His opinion contradicted the ideas of many contemporary philosophers of that time who believed that water, fire, air and earth were the four main elements from which all substances were created.
'Thought is the fountain of speech'
'I only know that I know nothing'
Known for his dialectic method of inquiry or method of 'elenchus'.
'No man ever steps in the same river twice, for it's not the same river and he's not the same man.'
The meaning of this quote, is that everything constantly changes, so that when one steps on a river, other waters flow on to him. In the same sense, man, as a living organism, is never the same.
'Why not whip the teacher when the pupil misbehaves? '
One of the founders of Cynic Philosophy. Also known for walking around in full daylight with a lamp; when asked what he was doing, he would answer, 'I am just looking for an honest man.'
'Nothing is more active than thought, for it travels over the universe, and nothing is stronger than necessity for all must submit to it.'
Is also known as the 'Father of Science'.
'The reason we have two ears and only one mouth, is that we may hear more and speak less.'
Founder of the Stoic School of Philosophy
'First learn the meaning of what you say and then speak'
According to this philosopher, all external events are determined by fate, and are thus beyond our control, but we can accept whatever happens calmly and dispassionately. Individuals, however, are responsible for their own actions, which they can examine and control through rigorous self-discipline.
'Of all things the measure is man, of the things that are, that they are, and of things that are not, that they are not.'
The meaning of this quote, is most likely interpreted as such: If Mr. A says “it is hot,” then the statement is true as far as he is concerned. Another person, Mr. B may simultaneously claim “it is cold.” This statement could also be true for him. Thus, the measure of hotness or coldness is fairly obviously the individual person.
'Wise men talk because they have something to say; fools, because they have to say something.'
Student of Socrates, known for his 'Socratic dialogues'
'The wise are instructed by reason, average minds by experience, the stupid by necessity and the brute by instinct.'