What is a monster? A being whose survival is incompatible with the existing order.
Interpretation
A monster is defined as something that cannot coexist within the current societal structures.
Denis Diderot's quote reflects on the nature of monsters as beings that challenge or disrupt the established norms and order of society. This could apply to individuals or ideas that are seen as threats because they do not conform to the accepted ways of living or believing, ultimately leading to conflict between the entity and its environment.
In practice
In a debate about societal norms, one might reference this quote to illustrate how individuals or ideas that challenge the status quo are often labeled as 'monsters'.
The arbitrary rule of a just and enlightened prince is always bad. His virtues are the most dangerous and the surest form of seduction: they lull a people imperceptibly into the habit of loving, respecting, and serving his successor, whoever that successor may be, no matter how wicked or stupid.
This root [the potato], no matter how much you prepare it, is tasteless and floury. It cannot pass for an agreeable food, but it supplies a food sufficiently abundant and sufficiently healthy for men who ask only to sustain themselves. The potato is criticized with reason for being windy, but what matters windiness for the vigorous organisms of peasants and laborers?
Do you see this egg? With this you can topple every theological theory, every church or temple in the world.
There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.
In order to get as much fame as one's father one has to much more able than he.
All abstract sciences are nothing but the study of relations between signs.
A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.
Life is infinitely stranger than anything which the mind of man could invent.
I say to my breath once again, little breath come from in front of me, go away behind me, row me quietly now, as far as you can, for I am an abyss that I am trying to cross.
You become responsible, forever, for what you have tamed.
All too often when liberals cite statistics, they forget the statisticians' warning that correlation is not causation.
Can we ring the bells backward? Can we unlearn the arts that pretend to civilize, and then burn the world? There is a march of science; but who shall beat the drums for its retreat?
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