Sacred Cow

A sacred cow is a firmly held belief that is rarely questioned and is largely exempt from criticism or opposition.

Sacred cows are a matter of opinion. One person's sacred cow is another's time-tested wisdom. Ideas labeled as sacred cows typically reflect one's ideology. While some may apply this label to the free market or to corporations, others put the minimum wage or government programs into this category.

In investing and elsewhere, the term is often used to dismiss an idea that an author is arguing against. Some examples of ideas labeled sacred cows in finance include: mutual funds, dividend investing, saving 15% of one's income for retirement, financial planning and Morningstar's style box. Ideas that are labeled sacred cows may also be referred to as "myths."