The idea of concurrent list in the Indian Constitution was borrowed from Australia.

Explanation:
The Indian Constitution, enacted in 1950, is a comprehensive document that lays down the framework for the functioning of the Indian government. It is a unique blend of ideas and principles from various sources, including the constitutions of different countries.

The concept of a "concurrent list" is one such idea that was borrowed from the Australian Constitution. The concurrent list is a legislative list that contains subjects on which both the central government and the state governments have the power to make laws. In other words, it is a shared jurisdiction where both the center and the states can legislate on matters mentioned in this list.

The idea of a concurrent list was introduced in the Indian Constitution to strike a balance between the powers of the central government and the state governments. It was seen as a way to ensure cooperation and coordination between the two levels of government in matters of national importance while also granting autonomy to the states.

The Australian Constitution, which was adopted in 1901, also includes a concurrent list. Like in India, this list contains subjects on which both the federal government and the state governments can legislate. The inclusion of a concurrent list in the Australian Constitution was aimed at promoting cooperation and uniformity in legislation across the country.

By borrowing the idea of a concurrent list from Australia, the framers of the Indian Constitution sought to address the complex nature of federalism in a diverse and vast country like India. It allows both the center and the states to legislate on certain subjects, ensuring a balance of power and preventing any one level of government from becoming too dominant.

In conclusion, the idea of a concurrent list in the Indian Constitution was borrowed from Australia. It is a significant feature that promotes cooperative federalism and ensures the harmonious functioning of the Indian government.