I prefer fact over 'belief'. If Marconi, Edison, Tesla, Einstein, had subscribed to 'belief' instead of intellectual/rational experiments/facts to devise solutions to real problems.
There is NO conflict between Faith and Reason. The conflict thesis is an old trope that some creaking old minds have not yet discarded.
Marconi: Catholic then Anglican. Among things he said:
The more I work with the powers of Nature, the more I feel God’s benevolence to man; the closer I am to the great truth that everything is dependent on the Eternal Creator and Sustainer [Creatore e Reggitore Eterno]; the more I feel that the so-called ‘science’ I am occupied with is nothing but an expression of the Supreme Will, which aims at bringing people closer to each other in order to help them better understand and improve themselves.....
I know how much you love and cherish the beautiful Nature - the expression of God’s Will - where one can find the ideal eternal values: the Truth, the Beauty and the Good (and you possess the three of them). The harmonious unity of causes and laws forms the Truth; the harmonious unity of lines, colors, sounds, and ideas forms the Beauty; while the harmony of emotions and the will forms the Good, which in being the ultimate expression of the Eternal and Supreme Creator brings man to completion and drives us to seek absolute perfection.
Edison: Deist that believed in the Supreme Intelligence. He said:
I believe in the existence of a Supreme Intelligence pervading the Universe.
We really haven't got any great amount of data on the subject, and without data how can we reach any definite conclusions? All we have — everything — favors the idea of what religionists call the "Hereafter." Science, if it ever learns the facts, probably will find another more definitely descriptive term.
Spoken shortly before Edison's death:
It is very beautiful over there!
What Henry Ford said of Edison:
He felt there was a central processing core of life that went on and on. That was his conclusion. We talked of it many times together . . . Call it religion or what you like, Mr. Edison believed that the universe was alive and that it was responsive to man's deep necessity. It was an intelligent and hopeful religion if there ever was one. Mr. Edison went away expecting light, not darkness.
But Thomas Alva Edison is probably the most agnostic one in the list you mentioned, in my opinion. Yet, only a few miles away from where I write this (I live near Edison's winter home) he attended this Congregationalist church which has long since been renamed in his honor:
http://www.edisonchurch.org/
Tesla: Advocated a religion based on the fusion of Christianity and Buddhism.
While I am not a believer in the orthodox sense, I commend religion, first, because every individual should have some ideal--religious, artistic, scientific, or humanitarian--to give significance to his life. Second, because all the great religions contain wise prescriptions relating to the conduct of life, which hold good now as they did when they were promulgated.
Einstein: A Deist, largely in the Spinozan mold. But he said, among many other things (all of these are seperate quotes):
I want to know how God created this world. I am not interested in this or that phenomenon, in the spectrum of this or that element. I want to know His thoughts, the rest are details.....
The most beautiful and most profound emotion we can experience is the sensation of the mystical. It is the sower of all true science. He to whom this emotion is a stranger, who can no longer stand rapt in awe, is as good as dead. That deeply emotional conviction of the presence of a superior Reasoning Power, which is revealed in the incomprehensible Universe, forms my idea of God....
Einstein didn't like how some atheists misused him in support of their views:
In view of such harmony in the cosmos which I, with my limited human understanding, am able to recognize, there are yet people who say there is no God. But what really makes me angry is that they quote me for the support of such views. ...
I can't answer with a simple yes or no. I'm not an atheist and I don't think I can call myself a pantheist. We are in the position of a little child entering a huge library filled with books in many different languages. The child knows someone must have written those books. It does not know how. The child dimly suspects a mysterious order in the arrangement of the books but doesn't know what it is. That, it seems to me, is the attitude of even the most intelligent human being toward God. We see a universe marvelously arranged and obeying certain laws, but only dimly understand these laws. Our limited minds cannot grasp the mysterious force that moves the constellations. I am fascinated by Spinoza's pantheism, but admire even more his contributions to modern thought because he is the first philosopher to deal with the soul and the body as one, not two separate things.
I'll say it again: I don't believe in Atheists.
BTS