Explanations:
When income is earned through salaries or wages, it is taxed when a tax return is filed. It will be subject to tax withholding (income taxes and social security taxes), so a taxpayer is using after-tax income to pay for personal expenses or investing.
If after-tax income is used for investments, and these investments experience capital appreciation, the growth on this investment is taxable if it is recognized (the investment is sold). The growth on the investment is new income (a new event) and it is taxed (at capital gain rates), not the original investment. The same is true with the sale of a business: the growth of the business is taxed, not the original investment.
The receipt of social security benefits also confuses people. One should look at social security taxes that are withheld from paychecks similarly to 401(k) contributions. These funds are taken out of paychecks, along with an employer match, and benefits are received at retirement. There is no double taxation because the social security benefits are a new event/new income that was funded by the social security taxes taken out of a person's paycheck over their working life.
It should be understood that events cause taxation. Earning salaries and wages produces income taxation and the sale of assets creates capital gain taxes. These are different events and have their own tax consequences.
For more clarity on taxes for individuals and businesses, contact LFC through the Contact Us feature on this blog.