"Another source of conviction in the existance of God connected with the reason and not the feelings, impresses me as having much more weight. This follows from the extreme difficulty or rather impossibility of conceiving this immense and wonderful universe, including man with his capability of looking far backwards and far into futurity, as the result of blind chance or necessity. When thus reflecting I feel compelled to look at a first cause having an intelliegent mind in some degree analogous to that of man; and I deserve to be called a theist.He adequately demonstrates his confusion by his confused writing, jumping from pro to con and back again multiple places.
This conclusion was strong in my mind about the time, as far I can remember, when I wrote the Origin of species; and it is since that time that it has very gradually with many fluctuations become weaker. But then arises the doubt -- can the mind of man, which has, as I fully believe, been developed from a mind as low as the possessed by the lowest animal, be trusted when it draws such a grand conclusions? May not these be the result of the connection between cause and effect which strikes us as a necessary one, but probably depends merely on inherited experience? Nor must we overlook the probability of the constant inculcation in a belief in God on the minds of children producing so strong and perhaps an inherited effect on their brains not yet fully developed, that it would be as difficult for them to throw off their belief in God, as for a monkey to throw off its instinctive fear and hatred of a snake.
I cannot pretend to throw the least light on such abstruse problems. The mystery of the beginning of all things is insoluble to us; and I for one must be content to remain an Agnostic."
1. It is "impossible" to consider man as "the result of blind chance or necessity".
2. Thus a "first cause having an intelligent mind" seems compelling.
3. Then, after a weakening, "arises the doubt -- can the mind of man, which has, as I fully believe, been developed from a mind as low as the possessed by the lowest animal, be trusted when it draws such a grand conclusions? May not these be the result of the connection between cause and effect which strikes us as a necessary one, but probably depends merely on inherited experience?"
In these two sentences, Darwin fluctuates from the issue of the necessity of Cause and Effect Determinism vs. rationality, to an excuse: "inherited experience". This is irrational, because if Cause and Effect Determinism exist, then rationality cannot be an "inherited experience", because all experience is predetermined by prior causes, not by internal cogitation.
He further digresses from Cause and Effect Determinism by appealing to "constant inculcation in a belief...", which has no bearing on the issue of Determinism vs. rationality. Finally, he dodges all issues:
4. "...the beginning of all things must remain a mystery..." And he asserts Agnosticism. But that mystery applies only if empirical data is the sole source of knowledge, and here Darwin executes his largest internal contradiction: He has asserted much story telling about why he believes evolution is Truth on the one hand; yet he cannot accept logical deduction of his own making against either evolution or Atheism on the other hand.
His standard for "evidence" varies considerably, depending upon what he wants to believe is True. In other words, his Agnosticism is emotional, because he rejects his own rational arguments contrary to evolution, out of hand, and without evidence.