Act decidedly and take the consequences. No good is ever done by hesitation.

— Thomas Henry Huxley

Agnosticism, in fact, is not a creed, but a method, the essence of which lies in the rigorous application of a single principle. That principle is of great antiquity; it is as old as Socrates; as old as the writer who said, 'Try all things, hold fast by that which is good'; it is the foundation of the Reformation, which simply illustrated the axiom that every man should be able to give a reason for the faith that is in him, it is the great principle of Descartes; it is the fundamental axiom of modern science. Positively the principle may be expressed: In matters of the intellect, follow your reason as far as it will take you, without regard to any other consideration. And negatively: In matters of the intellect, do not pretend that conclusions are certain which are not demonstrated or demonstrable. That I take to be the agnostic position, which is a man keep whole and undefiled, he shall not be ashamed to look the universe in the face, whatever the future may have in store for him. The results of the working out of the agnostic principle will vary according to individual knowledge and capacity, and according to the general condition of science. That which is unproved today may be proved, by the help of new discoveries, tomorrow. The only negative fixed points will be those negations which flow from the demonstrable limitation of our faculties. And the only obligation accepted is to have the mind always open to conviction. That it is wrong for a man to say he is certain of the objective truth of a proposition unless he can provide evidence which logically justifies that certainty. This is what agnosticism asserts and in my opinion, is all that is essential to agnosticism.

— Thomas Henry Huxley

All organisms vary. It is in the highest degree improbable that any given variety should have exactly the same relations to surrounding conditions as the parent stock. In that case it is either better fitted (when the variation may be called useful), or worse fitted, to cope with them. If better, it will tend to supplant the parent stock; if worse, it will tend to be extinguished by the parent stock. If (as it is hardly conceivable) the new variety is so perfectly adapted to the conditions that no improvement upon it is possible, —it will persist, because, though it does not cease to vary, the varieties will be inferior to itself. If, as it is more probable, the new variety is by no means perfectly adapted to its conditions, but only fairly well adapted to them, it will persist, so long as none of the varieties which it throws off are better adapted than itself. On the other hand, as soon as it varies in a useful way, i.e. when the variation is such as to adapt it more perfectly to its conditions, the fresh variety will tend to supplant the former.

— Thomas Henry Huxley

And those who will carefully study the so-called 'Mosaic code' contained in the books of Exodus, Leviticus, and Numbers, will see that, though Yahweh's prohibitions of certain forms of immorality are strict and sweeping, his wrath is quite as strongly kindled against infractions of ritual ordinances. Accidental homicide may go unpunished, and reparation may be made for willful theft. On the other hand, Na dab and Abide, who 'offered strange fire before Yahweh, which he had not commanded them,' were swiftly devoured by Yahweh's fire; he who sacrificed anywhere except at the allotted place was to be 'cut off from his people'; so was he who ate blood; and the details of the upholstery of the Tabernacle, of the millinery of the priests' vestments, and of the cabinet work of the ark, can plead direct authority from Yahweh, no less than moral commands.

— Thomas Henry Huxley

But anyone who is practically acquainted with scientific work is aware that those who refuse to go beyond fact, rarely get as far as fact; and anyone who has studied the history of science knows that almost every great step therein has been made by the 'anticipation of Nature,' that is, by the invention of hypotheses, which, though verifiable, often had very little foundation to start with.

— Thomas Henry Huxley

Can anyone deny that the old Israelites conceived Yahweh not only in the image of a man, but in that of a changeable, irritable, and, occasionally, violent man?

— Thomas Henry Huxley

Elohim was, in logical terminology, the genus of which ghosts, Che mosh, Dagon, Baal, and Yahweh were species. The Israelite believed Yahweh to be immeasurably superior to all other kinds of Elohim. The inscription on the Moab ite stone shows that King Mesa held Che mosh to be, as unquestionably, the superior of Yahweh.

— Thomas Henry Huxley

Extinguished theologians lie about the cradle of every science as the strangled snakes beside that of Hercules; and history records that whenever science and orthodoxy have been fairly opposed, the latter has been forced to retire from the lists, bleeding and crushed if not annihilated; scotched, if not slain.

— Thomas Henry Huxley

For once reality and his brains came into contact and the result was fatal.

— Thomas Henry Huxley

From the dawn of exact knowledge to the present day, observation, experiment, and speculation have gone hand in hand; and, whenever science has halted or strayed from the right path, it has been, either because its votaries have been content with mere unverified or unverifiable speculation (and this is the commonest case, because observation and experiment are hard work, while speculation is amusing); or it has been, because the accumulation of details of observation has for a time excluded speculation.

— Thomas Henry Huxley