Muhammad Tughluq was a medieval Indian scholar and a learned man. He knew logic, philosophy, mathematics, astronomy and physical sciences. He was also a calligraphist. He had knowledge of medicine and was skillful in dialectics.
Muhammad Tughluq has been described as an "amazing compound of contradictions". He is one of the most striking figures in medieval India. He was a man with ideas far beyond his age.
Tughluq was committed to maintaining the Sultanate's expansion into the newly-conquered provinces of peninsular India. To have better administration of these southern parts of the Empire, in the early part of his reign Tughluq moved the capital from Delhi to Devagiri, 700 miles south in the Deccan, renaming Devagiri as Daulatabad. Instead of moving just his government offices there, he forcibily moved the entire population of Delhi to the new capital. The plan failed due to inadequate water supply arrangements in Daulatabad; after only two years, the capital had to be shifted back again to Delhi. Large numbers of people died during the moves due to the inadequate travel arrangements. It was said that Delhi was a ghost town for years after the move back. "When I entered Dehli, it almost like a desert", wrote the North African traveller ibn Batuta.Tughluq also introduced token currency for the first time in India, modelled after the Chinese example, using brass or copper coins, backed by silver and gold kept in the treasury. However, very few people exchanged their gold/silver coins for the new copper ones and the tokens were easy to forge, which led to heavy losses. It is said that after the plan failed, there were heaps of copper coins lying around the royal offices for years.
Muhammad Bin Tughlaq is known for his active interest in experimenting with the coinage. He implanted his character and activities on his coinage and produced abundant gold coins compared to any of his predecessors. He overtook them by executing a fine calligraphy and by issuing number of fractional denominations. An experiment with his forced currency places him in the rank of one of the greatest moneyers of Indian history though it wasn't successful in India.
The large influx of gold due to his southern Indian campaign made him to adjust the weight standard of coinage which was in usage all the while. He added the gold dinar of weight 202 grains while compared to the then standard weight of 172 grains. The silver adlis weighed 144 grains weight and was his innovation aiming to adjust the commercial value of the metal with respect to gold. Seven years later, he discontinued it due to lack of popularity and acceptance among his subjects.
All his coins reflect a staunch orthodoxy. The coins stuck at both Delhi and Daulatabad, were curious and was issued in memory of his late father. The Kalima appeared in most of his coinage, the title engraved were "The warrior in the cause of God", "The trustier in support of the four Khalifs - Abubakkar, Umar, Usman and Ali". He minted coins in several places such as Delhi, Lakhnauti, Salgaun, Darul-I-Islam, Sultanpur (Warrangal), Tughlaqpur (Tirhut), Daulatabad(Devagiri), Mulk-I-Tilang etc., More than thirty varieties of bullion coins are known so far, and the types show his numismatic interests. The copper coins are not as fascinating as the bullion and gold coinage, and many were minted in a variety of fabrics.
Unique among his coinage was the "forced currency". Tughluq had two scalable versions, issued in Delhi and Daulatabad. The currency obeyed two different standards, probably to satisfy the local standard which preexisted in the North and in the South respectively. Tughluq's skill in forcing the two standards of currency is remarkable. He engraved "He who obeys the Sultan obeys the compassionate" to fascinate people in accepting the new coinage. Inscriptions were even engraved in the Nagari legend, but owing to the alloy used, the coinage underwent deterioration. As well, the Copper and Brass coins could easily be forged, turning every house into a mint. Tughluq subsequently withdrew the forged currency by exchanging it with bullion and gold.