Most Amer­i­can stu­dents in phi­los­o­phy live on a diet of ancient Greek phi­los­o­phy on the one hand, and then “mod­ern” phi­los­o­phy, which starts around the time of Descartes (the 17th cen­tu­ry), with numer­ous schools and approach­es spilling into the present day. If you get any­thing from between those ancient days and moder­ni­ty, it’s prob­a­bly some church­men, i.e. Augus­tine (from the 4th cen­tu­ry) and Thomas Aquinas (the 13th cen­tu­ry), with per­haps a few Romans thrown in there and (if you’re Jew­ish) Mai­monides (12th cen­tu­ry).

But a key part of this lin­eage was the East­ward turn that the great works of Greek and Roman phi­los­o­phy took dur­ing the so-called Dark Ages, when they were pre­served and copied in the Islam­ic world, and this peri­od pro­duced a wealth of phi­los­o­phy includ­ing two fig­ures who became influ­en­tial enough in the West that their names were Latinized: Ibn Sīnā (980‑1037 C.E.) and Ibn Rushd, a.k.a. Aver­roes (1126–1198). Aquinas was very famil­iar with these fig­ures and incor­po­rat­ed them into his influ­en­tial works, and in the case of Ibn Sina, at least, impor­tant fig­ures like John Locke had def­i­nite­ly known at least about his views, if not his actu­al works.

On the Par­tial­ly Exam­ined Life Phi­los­o­phy Pod­cast, which has been going for 13 years now, we range wide­ly over the his­to­ry of phi­los­o­phy but had not actu­al­ly cracked the Islam­ic world. Luck­i­ly, Ibn Sīnā is one of the favorite philoso­phers of one of our favorite guests, Peter Adam­son of King’s Col­lege Lon­don. Peter runs his own pod­cast, The His­to­ry of Phi­los­o­phy (With­out Any Gaps), which as the name implies, cov­ers Medieval phi­los­o­phy with admirable thor­ough­ness, cov­er­ing not only Ibn Sīnā and Ibn Rushd, but also fig­ures like al-Rāzī, al-Fārābī, Al-Ghazālī, and many oth­ers.

Peter was good enough to rec­om­mend some read­ings to intro­duce us and our lis­ten­ers to this fig­ure, some of which he actu­al­ly wrote. Because of the vol­ume, redun­dan­cy, and style of Ibn Sīnā’s writ­ings, some sort of guide to col­lect and to some degree explain pas­sages is essen­tial for get­ting a han­dle on this idio­syn­crat­ic and bril­liant thinker. He wrote at least three dif­fer­ent ver­sions of his all-encom­pass­ing sys­tem, which was influ­enced by and meant to sup­plant Aris­totle’s. In addi­tion to philosophical/theological top­ics, it includ­ed math­e­mat­ics, sci­ence, psy­chol­o­gy, and more. So instead of try­ing to read a whole work cov­er­ing all that, it makes more sense to pick indi­vid­ual top­ics and then look at the var­i­ous for­mu­la­tions he gave about these.

Our two top­ics for this dis­cus­sion were a pecu­liar argu­ment for the exis­tence of God — with impor­tant impli­ca­tions for talk­ing about meta­physics more gen­er­al­ly — and an argu­ment for the imma­te­ri­al­i­ty of the soul, which like­wise tells us a lot about the way that Ibn Sīnā thought about knowl­edge and its rela­tion to the world.

The argu­ment for the exis­tence of God was lat­er called by Thomas Aquinas “the argu­ment from con­tin­gency.” It posits that things in the world don’t sim­ply exist, but that they require some­thing else to sup­port their exis­tence. This isn’t a cause is the chrono­log­i­cal sense that we talk about it: a pri­or event that gave rise to the thing. Rather, the mate­r­i­al com­po­nents of some­thing in a cer­tain arrange­ment make it con­tin­ue to exist as that thing right now; for exam­ple, a house exists because its com­po­nent wood parts exist, with nails and such hold­ing them in place. And the wood in turn has its char­ac­ter because of its physical/chemical com­po­nents, etc. If these com­po­nent caus­es weren’t in place, the thing would not exist; the thing is thus “con­tin­gent,” mean­ing it might well not have exist­ed were it not for those caus­es.

This pic­ture of the uni­verse thus includes a giant net­work of causal­i­ty, but does that net­work itself rest on any­thing? Accord­ing to Ibn Sīnā, there must be some­thing that is not con­tin­gent that holds every­thing else up. But is this thing God (in the sense that a good Mus­lim of his time would rec­og­nize it)? Ibn Sīnā then has a long series of argu­ments to show one by one that just by being “the nec­es­sary being,” this enti­ty also must be unique, must be all-pow­er­ful, gen­er­ous, and all the oth­er things one would expect God to be.

The argu­ment for the immor­tal­i­ty of the soul is per­haps Ibn Sīnā’s most famous argu­ment, often called the fly­ing or float­ing man argu­ment. It’s a thought exper­i­ment where­by you imag­ine you’ve just been cre­at­ed, but ful­ly mature, so you can think, but with no mem­o­ry, and your sens­es are inop­er­a­ble. You can’t even feel grav­i­ty or the ground under your feet (thus the “fly­ing” part). Accord­ing to Ibn Sīnā, you would still in such a sit­u­a­tion know that you exist. Since your appre­hen­sion of self did not include any part of your body (you could­n’t feel your body at all), that is sup­posed to prove that your body is not an essen­tial part of what you are.

Ibn Sīnā thought this argu­ment defin­i­tive because of his the­o­ry of knowl­edge by which if you know any­thing at all, then you know about the essen­tial com­po­nents of that thing. If you know what a tri­an­gle is, you know that it’s an abstract geo­met­ri­cal fig­ure with three straight sides. If you know what a horse is, you know that it’s a bio­log­i­cal ani­mal with a par­tic­u­lar char­ac­ter that you can iden­ti­fy. And to know what you are essen­tial­ly, you only need know that feel­ing of your own mind; any­thing else about that mind being asso­ci­at­ed with a par­tic­u­lar body that lives in a par­tic­u­lar part of the world and is just knowl­edge of con­tin­gent, rela­tion­al facts about your­self.

PEL hosts Mark Lin­sen­may­er and Dylan Casey grap­ple in detail with Peter about these argu­ments, both on this record­ing and on a sec­ond part of the dis­cus­sion for those that want to hear more. To read more about these argu­ments and get the cita­tions to the texts we read for this dis­cus­sion, see the essay for this episode at partiallyexaminedlife.com. The His­to­ry of Phi­los­o­phy pod­cast also fea­tures four mono­logues and an inter­view about Ibn Sīnā. Don’t let this gap in your knowl­edge of major fig­ures in intel­lec­tu­al his­to­ry remain unfilled!

Mark Lin­sen­may­er is the host of the Par­tial­ly Exam­ined Life, Pret­ty Much Pop, and Naked­ly Exam­ined Music pod­casts. He is a writer and musi­cian work­ing out of Madi­son, Wis­con­sin. Read more Open Cul­ture posts about The Par­tial­ly Exam­ined Life.

Image by Solomon Grundy.