ber 21, 1613) a long and eloquent letter on the subject. The original of this letter was never found, although the Inquisition made diligent search for it. Many authentic copies were circulated, however.[1] The question of the place of the Bible in scientific questions is discussed. Galileo is a good Catholic; the scriptures can not lie or err, he says. But the expositors are fallible. They will fall into error, nay into heresy, if they interpret Holy Writ literally. Both scriptures and external nature owe their origin to the Divine Word.
“It was necessary, however, in Holy Scripture, in order to accommodate itself to the understanding of the majority to say many things which apparently differ from the precise meaning. Nature, on the contrary, is inexorable and unchangeable, and cares not whether her hidden causes and modes of working are intelligible to the human understanding or not, and never deviates from her prescribed laws.” It appears to me, therefore, says Galileo, that no effect of nature, which experience places before our eyes, or is the necessary conclusion derived from evidence, should be rendered doubtful by passages of Scripture which contain thousands of words admitting of various interpretations, for every sentence of Scripture is not bound by such rigid laws as is every effect of Nature. . . . Since two truths can obviously never contradict each other, it is the part of wise interpreters of Holy Scripture to take the pains to find out the real meaning of its statements in accordance with the conclusions regarding nature which are quite certain, either from the clear evidence of sense or from necessary demonstration. As therefore the Bible, although dictated by the Holy Spirit, admits. . . in many passages of an interpretation other than the literal one and as, moreover, we can not maintain with certainty that all interpreters are inspired by God, I think it would be the part of wisdom not to allow any one to apply passages of Scripture in such a way as to force them to support, as true, conclusions concerning nature, the contrary of which may afterwards be revealed by the evidences of our senses or by necessary demonstration. Who will set bounds to man's understanding? Who can assure us that everything that can be known in the world is known already?. . . I am inclined to think that the authority of Holy Writ is intended to convince men of those truths which are necessary for their salvation which, being far above man's understanding can not be made credible by any learning, or by any other means than revelation by the Holy Spirit. But that the same God who has endowed us with senses, reason and understanding, does not permit us to use them and desires to acquaint us in any other way with such knowledge as we are in a position to acquire for ourselves by means of those faculties, that it seems to me I am not bound to believe, especially concerning those sciences about which the Holy Scriptures contain only small fragments and varying conclusions; and this is precisely the case with astronomy, of which there is so little that the planets are not even all enumerated
This noble declaration of the independence of man's reason, written in 1613, marks the highest insight yet reached by the human spirit in this regard. It is the greatest product of Galileo's philosophical genius. It was written in haste, he says, yet its form is perfect and
- ↑ The letter was subsequently expanded and addressed in its new form to the Grand Duchess Christine (1614).
