Friedrich Nietzsche, answered from the texts and cited to the page.
The distinction cuts at the root of all moral valuation. Every morality originates from one of two sources: either a ruling group that determines value out of its own fullness, or a subjected group that determines value out of its own suffering and need for revenge.1 The noble type does not look outward first. It affirms itself — its own strength, its own pride, its own exalted states of soul — and only as an afterthought, a pale contrasting shade, produces a concept of "bad" to describe what it despises: the cowardly, the petty, the anxious, the groveling, the liars.2
What it despises it does not hate; it looks down with something closer to impatience, even joyfulness — contempt is too light a thing to transform its object into a genuine monster.3 The noble human being is value-creating; it needs no approval from outside itself, judges "what is harmful to me is harmful in itself," and honors in others what it recognizes as part of itself.4
In the foreground always is the feeling of fullness, of power that seeks to overflow. Ressentiment (reactive resentment) works the opposite mechanism entirely. Slave morality begins not with affirmation but with negation — a No directed outward at what is "different," what is "not itself." Because those who feel ressentiment are denied the true reaction of deeds, they compensate with imaginary revenge; their action is fundamentally reaction, requiring a hostile external world to define themselves against at all.56
The "evil" they project onto their enemies is not a pale afterthought but the original creative deed — and who is this "evil" one? Precisely the good man of noble morality, the powerful, the ruling, the strong, seen now through a venomous eye and reinterpreted in another color.7 The moral vocabulary itself betrays the difference. For master morality, "good" and "bad" map onto "noble" and "contemptible." For slave morality, "good" and "evil" carry an entirely different charge: the "evil" one inspires fear, and that fear is the measure of his power; the slave's "good" man must be undangerous, easy to deceive, a little stupid perhaps — the languages even begin to draw "good" and "stupid" closer together wherever slave morality becomes preponderant.8
One should not flatten this into a simple historical sequence, as if one type ruled the ancient world and the other rules ours. In more mixed cultures the two moralities interpenetrate, misunderstand each other, and sometimes coexist within a single soul.9 That is precisely the condition of modern Europeans — and it is what makes modern moral psychology so tortured, so hypocritical, so ripe for genealogical dissection.
The moral discrimination of values has originated either among a ruling group whose consciousness of its difference from the ruled group was accompanied by delight — or among the ruled, the slaves and dependents of every degree.Beyond Good and Evil, pp. 204–205
he despises them... One feels contempt for the cowardly, the anxious, the petty, those intent on narrow utility; also for the suspicious with their unfree glances, those who humble themselves, the doglike people who allow themselves to be maltreated, the begging flatterers, above all the liars.Beyond Good and Evil, pp. 204–205
there is indeed too much carelessness, too much taking lightly, too much looking away and impatience involved in contempt, even too much joyfulness, for it to be able to transform its object into a real caricature and monster.On the Genealogy of Morals, pp. 44–45
The noble type of man experiences itself as determining values; it does not need approval; it judges, 'what is harmful to me is harmful in itself'; it knows itself to be that which first accords honor to things; it is value-creating.Beyond Good and Evil, pp. 204–205
while every noble morality develops from a triumphant affirmation of itself, slave morality from the outset says No to what is 'outside,' what is 'different,' what is 'not itself'; and this No is its creative deed.On the Genealogy of Morals, pp. 44–45
The slave revolt in morality begins when ressentiment itself becomes creative and gives birth to values: the ressentiment of natures that are denied the true reaction, that of deeds, and compensate themselves with an imaginary revenge.On the Genealogy of Morals, pp. 44–45
precisely the 'good man' of the other morality, precisely the noble, powerful man, the ruler, but dyed in another color, interpreted in another fashion, seen in another way by the venomous eye of ressentiment.On the Genealogy of Morals, pp. 48–49
According to slave morality, those who are 'evil' thus inspire fear; according to master morality it is precisely those who are 'good' that inspire, and wish to inspire, fear, while the 'bad' are felt to be contemptible... Wherever slave morality becomes preponderant, language tends to bring the words 'good' and 'stupid' closer together.Beyond Good and Evil, pp. 207–208
yet more often the interpenetration and mutual misunderstanding of both, and at times they occur directly alongside each other — even in the same human being, within a single soul.Beyond Good and Evil, pp. 204–205