What can I know? What ought I to do? What may I hope?

[Aristotle formal logic thus far (1787)] has not been able to advance a single step, and hence is to all appearances closed and completed.

Animals... are there merely as a means to an end. That end is man.

If, like Hume, I had all manner of adornment in my power, I would still have reservations about using them. It is true that some readers will be scared off by dryness. But isn't it necessary to scare off some if in their case the matter would end up in bad hands?

Maximum individuality within maximum community

If you punish a child for being naughty, and reward him for being good, he will do right merely for the sake of the reward; and when he goes out into the world and finds that goodness is not always rewarded, nor wickedness always punished, he will grow into a man who only thinks about how he may get on in the world, and does right or wrong according as he finds advantage to himself.

In the mere concept of one thing it cannot be found any character of its existence.