"The human mind is a wonderful machine; but it is also a very delicate one."

"The true philosopher is he who is always learning, and who is never ashamed to confess his ignorance."

"I shall not attempt to give a detail of all the cases that have come under my observation, but shall select a few of the most striking, and such as will, I trust, be sufficient to convince the candid …"

"The progress of science is slow, but it is sure."

"The disease has hitherto been confined to particular districts; and it has been observed, that where the Cow Pox has prevailed, the Small Pox has been much less frequent, and much less fatal."