What term defines the public understanding and certainty over tax liabilities?

The term that defines the public understanding and certainty over tax liabilities is simplicity. When a tax system is simple, it means that taxpayers can easily understand their obligations, making it clear what they need to pay and when. This clarity promotes compliance and minimizes confusion about tax rates and regulations, thus fostering a sense of trust and predictability in the tax system. Simplicity is crucial because it reduces the costs associated with tax preparation and compliance for individuals and businesses alike, leading to higher levels of tax compliance and overall efficiency within the tax system.

In contrast, tax evasion refers to illegal practices to escape paying taxes, which does not contribute to public understanding or certainty. A progressive tax system, while equitable in nature, does not specifically address the clarity of tax liabilities. Vertical equity pertains to the fairness of the tax burden among different income levels but also does not ensure that tax rules are understood or straightforward for the public. Therefore, simplicity is the best term that encapsulates a clear and certain understanding of tax liabilities among the populace.