Knowledge of the External World
, p. 95
, or WORTH of a man, is as of all things, his price; that is to say, as much so would be given for
the use of his power:
therefore  is not absolute;
but  a thing dependent on the
need and judgment of another.
Leviathan, English Works
, 3, p. 76
 The only proof capable of being given that an object is visible is that people actually see it.
The only proof that a sound is audible is that people hear it:
 and so of the other sources of our
In like manner,
I apprehend,  the sole evidence it is possible to produce that anything
is desirable is that people do actually desire it.
John Stuart Mill
Utilitarianism, Collected Works,
X, p. 234
 It is better to be a human being dissatisfied than a pig satisfied;
 better to be Socrates
dissatisfied than a fool satisfied.
And  if the fool, or the pig, is of a different opinion, it is
because they only know their own side of the question.
John Stuart Mill
Utilitarianism, p. 212
 If the facts of experience—facts about what it is like
the experiencing organism--are accessible only
from one point of view, then it is a mystery how the true character of experiences could be revealed in the
physical operation of that organism.
 The latter is a domain of objective facts
the kind that can be observed and understood from many points of view and by individuals with differing
Thomas Nagel “What is it Like to be a Bat?”
, p. 172
 Everything necessarily is or is not, and will be or will not be; but one cannot divide and say that one or the
other is necessary.
for example:  it is necessary for there to be or not to be a sea-battle
tomorrow; but it is not necessary for a sea-battle to take place tomorrow, nor for one not to take place--
though it is necessary for one to take place or not to take place….