Animals manifestly enjoy excitement, and suffer from annul and may exhibit curiosity.

Do not undertake the program unless the goal is manifestly important and its achievement nearly impossible.

I look upon a good physician, not so properly as a servant to nature, as one, that is a counsellor and friendly assistant, who, in his patient’s body, furthers those motions and other things, that he judges conducive to the welfare and recovery of it; but as to those, that he perceives likely to be hurtful, either by increasing the disease, or otherwise endangering the patient, he thinks it is his part to oppose or hinder, though nature do manifestly enough seem to endeavour the exercising or carrying on those hurtful motions.

It is better for all the world, if instead of waiting to execute degenerate offspring for crime, or to let them starve for their imbecility, society can prevent those who are manifestly unfit for continuing their kind. The principle that sustains compulsory vaccinations is broad enough to cover cutting Fallopian tubes. Three generations of imbeciles are enough.

It is obvious that man dwells in a splendid universe, a magnificent expanse of earth and sky and heaven, which manifestly is built on a majestic plan, maintains some mighty design, though man himself cannot grasp it. Yet for him it is not a pleasant or satisfying world. In his few moments of respite from labor or from his enemies, he dreams that this very universe might indeed be perfect, its laws operating just as now they seem to do, and yet he and it somehow be in full accord. The very ease with which he can frame this image to himself makes the reality all the more mocking. ... It is only too clear that man is not at home in this universe, and yet he is not good enough to deserve a better.

It may be observed of mathematicians that they only meddle with such things as are certain, passing by those that are doubtful and unknown. They profess not to know all things, neither do they affect to speak of all things. What they know to be true, and can make good by invincible arguments, that they publish and insert among their theorems. Of other things they are silent and pass no judgment at all, chusing [choosing] rather to acknowledge their ignorance, than affirm anything rashly. They affirm nothing among their arguments or assertions which is not most manifestly known and examined with utmost rigour, rejecting all probable conjectures and little witticisms. They submit nothing to authority, indulge no affection, detest subterfuges of words, and declare their sentiments, as in a Court of Judicature [Justice], without passion, without apology; knowing that their reasons, as Seneca testifies of them, are not brought to persuade, but to compel.

Take an arrow, and hold it in flame for the space of ten pulses, and when it cometh forth you shall find those parts of the arrow which were on the outsides of the flame more burned, blacked, and turned almost to coal, whereas the midst of the flame will be as if the fire had scarce touched it. This is an instance of great consequence for the discovery of the nature of flame; and sheweth manifestly, that flame burneth more violently towards the sides than in the midst.

The remotest discoveries of the Chemist, the Botanist, or the Mineralogist, will be as proper objects of the Poet’s art as any upon which it can be employed, if the time should ever come when these things shall be familiar to us, and the relations under which they are contemplated by the followers of these respective sciences shall be manifestly and palpably material to us as enjoying and suffering beings.

There is no fundamental difference between man and the higher animals in their mental faculties ... The lower animals, like man, manifestly feel pleasure and pain, happiness, and misery.

To show, therefore, that we are capable of knowing, i.e. being certain that there is a God, and how we may come by this certainty, I think we need go no further than ourselves, and that undoubted knowledge we have of our own existence... For man knows that he himself exists... If any one pretends to be so sceptical as to deny his own existence, (for really to doubt of it is manifestly impossible,) let him for me enjoy his beloved happiness of being nothing, until hunger or some other pain convince him of the contrary... He knows also that nothing cannot produce a being; therefore something must have existed from eternity... Next, it is evident, that what had its being and beginning from another, must also have all that which is in and belongs to its being from another too. All the powers it has must be owing to and received from the same source. This eternal source, then, of all being must also be the source and original of all power; and so this eternal Being must be also the most powerful... And most knowing. Again, a man finds in himself perception and knowledge. We have then got one step further; and we are certain now that there is not only some being, but some knowing, intelligent being in the world. There was a time, then, when there was no knowing being, and when knowledge began to be; or else there has been also a knowing being from eternity...And therefore God.

We [may] answer the question: “Why is snow white?” by saying, “For the same reason that soap-suds or whipped eggs are white”—in other words, instead of giving the reason for a fact, we give another example of the same fact. This offering a similar instance, instead of a reason, has often been criticised as one of the forms of logical depravity in men. But manifestly it is not a perverse act of thought, but only an incomplete one. Furnishing parallel cases is the necessary first step towards abstracting the reason imbedded in them all.