But to manipulate men is to deny their human essence

Two Concepts of Liberty (1958) by Isaiah Berlin. Select quotes.

Everything is what it is: liberty is liberty, not equality or fairness or justice or culture, or human happiness or a quiet conscience.

[snip]

But to manipulate men, to propel them towards goals which you — the social reformer — see, but they may not, is to deny their human essence, to treat them as objects without wills of their own, and therefore to degrade them.

[snip]

All forms of tampering with human beings, getting at them, shaping them against their will to your own pattern, all thought control and conditioning is, therefore, a denial of that in men which makes them men and their values ultimate.

[snip]

I am normally said to be free to the degree to which no man or body of men interferes with my activity. Political liberty in this sense is simply the area within which a man can act unobstructed by others. If I am prevented by others from doing what I could otherwise do, I am to that degree unfree; and if this area is contracted by other men beyond a certain minimum, I can be described as being coerced, or, it may be, enslaved. Coercion is not, however, a term that covers every form of inability. If I say that I am unable to jump more than ten feet in the air, or cannot read because I am blind, or cannot understand the darker pages of Hegel, it would be eccentric to say that I am to that degree enslaved or coerced. Coercion implies the deliberate interference of other human beings within the area in which I could otherwise act.

If, as I believe, the ends of men are many, and not all of them are in principle compatible with each other, then the possibility of conflict — and of tragedy — can never wholly be eliminated from human life, either personal or social. The necessity of choosing between absolute claims is then an inescapable characteristic of the human condition. This gives its value to freedom as Acton conceived of it — as an end in itself, and not as a temporary need, arising out of our confused notions and irrational and disordered lives, a predicament which a panacea could one day put right.