In the two volumes issued in English by Waite in 1894, there is much that is difficult to read and to appreciate from our modern standpoint.

In the book "Concerning Long Life" he confesses that his method and practice will not be intelligible to common persons and that he writes only for those whose intelligence is above the average.

To those fond of transcendental studies they appeal and are perhaps intelligible.

Everywhere one comes across shrewd remarks which prove that Paracelsus had a keen belief in the all-controlling powers of nature and of man's capacity to make those powers operate for his own good: "the wise man rules Nature, not Nature the wise man." "The difference between the Saint and the Magus is that the one operates by means of God, and the other by means of Nature." He had great faith in nature and the light of nature, holding that man obtains from nature according as he believes.

His theory of the three principles appears to have controlled his conception of everything relating to man, spiritually, mentally and bodily; and his threefold genera of disease corresponded in some mysterious way with the three primary substances, salt, sulphur and mercury.
How far he was a believer in astrology, charms and divination it is not easy to say.