Twenty-seven letters written by Albert Einstein are auctioning later today, for an estimated $1m.
Selling in single lots, the letters offer fascinating insight into one of history's greatest minds, as he tackles a range of subjects.
One letter he wrote to his children in 1923 discusses his flight from Germany. "I'm sitting here quietly in Holland after I was informed that there are certain people in Germany who are after me as a 'Jewish Holy Man'," he writes.
Signed "Papa", it has a $15,000 valuation ahead of the Profiles In History auction in Los Angeles.
In another, to his ex-wife Mileva Maric, he states: "The Relativity Theory has now been experimentally proven, but the issue of the connection of gravitation and electricity is shipwrecked, at least in my opinion. Theoretical physics is currently enormously thorny." The 1926 note will sell for an expected $30,000.
And in a $25,000-estimated 1949 letter to a Jesuit priest, Einstein discusses his agnosticism.
"I have repeatedly said that in my opinion the idea of a personal God is a childlike one," he writes.
"I prefer an attitude of humility corresponding to the weakness of our intellectual understanding of nature and of our own being."
Einstein letters are hugely popular with collectors.
Earlier this year, a letter he wrote concerning relativity and God auctioned for $75,000, while 2012 saw his famous "God letter" sell for $3m.
Joe Maddalena, chief executive of the auction house, comments: "We have amassed an extremely magnificent group of personal and profound handwritten Einstein letters covering a vast amount of subject matter.
"These letters depict his inner most views, offering intriguing content as only Einstein can. This collection is an embodiment of the physicist life's work."
Check out our own fascinating Albert Einstein-signed letter for sale.
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