Ṣadr ad-Dīn Muḥammad Shīrāzī, more commonly known as Mullā Ṣadrā[1] (Persian: ملا صدرا; Arabic: صدر المتألهین; c. 1571/2 – c. 1635/40 CE / 980 – 1050 AH), was a Persian[2][3][4][5] Twelver Shi'i Islamic mystic, philosopher, theologian, and ‘Ālim who led the Iranian cultural renaissance in the 17th century.

According to Oliver Leaman, Mulla Sadra is arguably the single most important and influential philosopher in the Muslim world in the last four hundred years.

His main work is The Transcendent Philosophy of the Four Journeys of the Intellect, or simply Four Journeys, In which he attempted to reach Sufism and prove the idea of Unity of Existence by offering a new intake and perspective on Peripatetic philosophy that was offered by Alpharabius and Avicenna in the Islamic world.

Sadra was a very intelligent, strict, energetic, studious, and curious boy and mastered all the lessons related to Persian and Arabic literature, as well as the art of calligraphy, during a very short time.

Following old traditions of his time, and before the age of puberty, he also learned horse riding, hunting and fighting techniques, mathematics, astronomy, some medicine, jurisprudence, and Islamic law.

[10] In 1591, Mulla Sadra moved to Qazvin and then, in 1597, to Isfahan to pursue a traditional and institutional education in philosophy, theology, Hadith, and hermeneutics.

[12] Shaykh Baha was an expert in Islamic sciences but also a master of astronomy, theoretical mathematics, engineering, architecture, medicine, and some fields of secret knowledge.

[13] After he had finished his studies, Sadra began to explore unorthodox doctrines and as a result was both condemned and excommunicated by some Shi'i ʿulamāʾ.

He then retired for a lengthy period of time to a village named Kahak, near Qom, where he engaged in contemplative exercises.

[9] During his time in Shīrāz, Ṣadrā began writing treatises that synthesized wide-ranging strands of existing Islamic systems of thought at Khan School.

Although Ṣadrā's influence remained limited in the generations after his death, it increased markedly during the 19th century, when his ideas helped inspire a renewed Akhbārī tendency within Twelver Shīʿism.

[16] The advantage to this schema is that it is acceptable to the fundamental statements of the Qur'an,[citation needed] even as it does not necessarily undermine any previous Islamic philosopher's Aristotelian or Platonic foundations.

One result of Sadra's existentialism is "The unity of the intellect and the intelligible" (Arabic: Ittihad al-Aaqil wa l-Maqul.

Within this perspective we can perceive what Sadra meant by the unitive union of the human soul, in the supreme awareness of its acts of knowledge, with the active Intelligence which is the Holy Spirit.

[18]Another central concept of Mulla Sadra's philosophy is the theory of "substantial motion" (Arabic:al-harakat al-jawhariyyah), which is "based on the premise that everything in the order of nature, including celestial spheres, undergoes substantial change and transformation as a result of the self-flow (sarayan al-wujud) and penetration of being (fayd) which gives every concrete individual entity its share of being.

In contrast to Aristotle and Avicenna who had accepted change only in four categories, i.e., quantity (kamm), quality (kayf), position (wad) and place (ayn), Sadra defines change as an all-pervasive reality running through the entire cosmos including the category of substance (jawhar).