Cambridge, May 18, 1873.

... I cannot object to your maintaining the hypothesis that each and every existing plant and animal form has been directly created (or mediately created, if you see a difference) out of the soil, pure hypothesis though it be, and one which “from the nature of the case can never be directly proved.” It is natural that you should hold to such hypothesis as long as you believe it to be possibly tenable.

But what I may ask you very seriously to consider is, whether you are prepared to bear the responsibility you assume in maintaining and teaching that no hypothesis of the derivation of existing “specific” forms from previous ones more or less like them can logically be theistic and religious. How far any such hypothesis may be probable or tenable in view of the evidence is not the question raised, but a far more momentous one.

Consider what the “younger men who learn of you” will be likely to think when they come to discard, as the best informed ones probably will after a while, your scientific views on this subject; but still, perchance, confide in your dictum that the doctrine of the derivative origin of one species from another cannot logically stop short of “blank materialism, destructive both of science and religion, and even ... to morals and social organization.”

There will be “a heavy penalty to pay,” but there are two sides to the question as to who is to pay a part of it. What I said in the last paragraph of the Dubuque address “we need not here consider”[92] is, nevertheless, worthy of consideration.

The time is not very distant, I imagine, when those who have protested against such reckless statements will be thought to have done some service to religion as well as to science.

I trust that the foundations of theism and of the Christian religion rest upon firmer foundations than the so-called “immutability of species.”

TO A. DE CANDOLLE.

Cambridge, June 12, 1873.

My dear de Candolle,—I must be in your eyes a disgracefully negligent correspondent and an ungrateful friend. I think, however, that I must have acknowledged the arrival of your volume which I received, I think, in March,—more likely late in February. The attempt at a perusal of it was when, on the 12th March, I went on to New York to pay the last duties to my venerable and good friend and associate, Dr. Torrey. I read a good part of the volume on the railway journeys, and planned a review of several of the articles. Then, a month later, I broke away from my laborious life here, and made a visit to my old friend Professor Henry, at Washington. I even went as much farther south, to Wilmington, North Carolina, where I met the spring in all its beauty, a month in advance of our tardy north. I collected a lot of live Dionæas, etc. I returned to a great accession of university work, my assistant being obliged to leave me on the 1st of May.