Which are the three forces that are responsible for an economy's attainment of a steady state according to neoclassical theory?

1. Savings and investment: According to neoclassical theory, savings and investment play a crucial role in an economy's attainment of a steady state. Savings provide the funds for investment, which in turn leads to the accumulation of capital and the growth of the economy.

2. Technological progress: Technological progress is another key force that drives an economy towards a steady state. Advances in technology lead to increases in productivity, which in turn drive economic growth and development.

3. Population growth: Population growth is also considered a significant factor in an economy's attainment of a steady state. A growing population can lead to increased demand for goods and services, which can drive economic growth. However, excessive population growth can also put pressure on resources and lead to economic instability.

1. Diminishing Returns: As an economy accumulates more capital and labor, the marginal product of each additional unit of capital or labor decreases. This means that each additional unit of input produces less output, which slows down growth.
2. Population Growth: As an economy's population grows, the supply of labor increases. This can lead to a decrease in wages, which reduces consumer spending and investment, and thus slows down growth.
3. Technological Progress: Technological progress can lead to an increase in the productivity of labor and capital, which can increase output and growth. However, technological progress can also lead to the obsolescence of existing capital and labor, which can reduce output and growth in the short-run.