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Correspondence between Ibn Sina and Al-Biruni
by Meam Wye
Al-Biruni began this debate by qutestioning certain Aristotle's theories. Ibn Sina replied in a scholarly manner but Al-Biruni was not satisfied with his answers. Al-Biruni replied back criticzing each answer that he had received by giving his own logical arguments and at the same time asking him further questions. This exchange of letters resulted in a written debate in which Al-Biruni asked Ibn Sina a total of 18 questions. In the later stages, Ibn Sina asked one of his prominent student, Ahmad ibn Ali al-Masumi to reply on his behalf.
As an example, following is an initial exchange of questions/answers between these two great polymaths related to Vision.
Al-Biruni:
How is vision possible? Why can we see beneath water whereas the ray of vision reflects off opaque bodies and the surface of water is opaque?
Ibn Sina:
According to Aristotle, vision is not the result of the rays coming out of the eye; that is Plato's view. Although, upon examination, one finds that there is no [real] difference between the sayings of the two, for Plato said this for the commoners in their slang. This has been explained by Shaikh Abu Nasr al-Farabi this in his book al-Jam bayna Ra'yain al-Hakimin (The Concordance Between the Opinions of the Two Wise Ones). In Aristotle's opinion, vision results from the contact of the vitreous humor(al-ratubatul jalidiyyah) of the eye with the transparent surface; [upon contact, vitreous humor] picks up the colors that are facing it at the parallel point of the body of which the color is the property. Since the vitreous humor is transparent, it would change and react to this color. And when this gelatinous substance changes, it becomes the instrument through which the faculty of vision perceives, this faculty recognizes the reaction that occurs and that is how vision becomes possible. There are more details about it in the commentaries on Book II of Kitab al-Nafs (On the Soul) by the Philosopher and [in the commentaries] on his Kitab al-Hiss (Sense and Sensibilia). So if that was that, and [since] water and air are transparent bodies presenting the nature of colors to the senses, doubt should disappear.
Al-Biruni:
Your answer presented Aristotle's definition of the vision but not the explanation, and sometimes the definition of a thing requires many different interpretations. According to what you said, the one who sees would not be able to distinguish between dimensions, and [as such] he will perceive small [objects] nearby to be identical to large distant [objects]; and so too would be the case with sounds: loud sounds further away would be heard just as would quiet sounds closer by, the listener being unable to distinguish between the different sounds from their sources. If the transparent [body] were affected by color, then a glass stained with black on one side when looked upon through any other side--except from the side opposite to the blackened side--should look black. The question was not about perception of what is under the surface of water, but I had asked [rather] about the understanding of how vision penetrates based upon the understanding of reflection of the rays simultaneously under the surface of water.
Ibn Sina and and later his student had replied again, and in much more detail, to the criticism above. The purpose of quoting here this initial correspondence, related to vision, was simply to get a glimpse of the analytical approaches of the two great minds.
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September 20, 2009 9:15 PM
An intriguing beginning look At what must be a fascinating conversation between these two thinkers. I hope you have more in future posts. It's like tuning in to someone's conversation and not wanting to leave until they're finished, no matter how long it takes.
September 21, 2009 12:30 PM
very cute and interesting how they wrote back and forth in a debate almost. It would be fascinating to be able to read all the letters.
Wow, I really wished that I could read more so I knew exactly what they were discussing. It's hard with my situation.
September 22, 2009 5:30 AM
I agree Mr.George Polley. It's indeed quite fascinating and one feel like being taken 1000 years back :) I kept the post short as I thought that the detail might be boring for many and also because I wasn't sure about the copyright issues of the English translation. Thanks for your feedback.
September 22, 2009 5:56 AM
Thanks Tricia for your comment. It's quite interesting to read but I found it difficult to fully understanding the conversation. Many questions were related to Philosophy and Astronomy and these are definitely not my areas of knowledge. I am now able to appreciate the great works done by the Historians of Science including George Satron (Father of History of Science)!
September 23, 2009 5:23 AM
Hi Meam,
Thankyou for leaving a lovely comment at TheRainbowBank,for my daughter.
Your site is beautiful.If it wasn't for Islam the renaissance would probably have not happened.
Kind regards
Simon
September 24, 2009 12:19 AM
Thanks Simon! I feel that every civilization has made and will make its own unique contributions. Hadn't it been for the west, we wouldn't have been able to share and discuss this online :)
September 25, 2009 7:41 AM
Hi,
Thanks for joining my blog!
It's interesting - my graduate thesis in geography was on the topic of Moslem geography and the role it played in helping to spawn Europe's Renaissance. I remember reading about Ibn Sina! Fascinating times.
~Donna
September 25, 2009 7:58 AM
Thanks for stopping by and sharing your thoughts :)
October 9, 2009 7:43 AM
I visit your blog very often.
You got soo much information in here.
its a good writeup.
keep posting :)
October 10, 2009 1:02 PM
Thank you for your encouraging comment.
November 29, 2009 8:10 AM
Thank you for the great article!
I was wondering if you know if there exists any books (in english) which has collected the whole correspondenve between Al-Biruni and Ibn Sina?
All good,
Kjersti
November 30, 2009 7:17 AM
The only available English translation, that I know of, is that by Rafik Berjak & Muzaffar Iqbal, published as as series of articles in 'Islam & Science'; the first one dated June 2003 and the last one (probably the 8th article in the series) dated June 2007.
July 4, 2011 12:07 PM
I hope there will be more quotation about their conversation...
^_^